A battery separator comprises a carrier web of non-woven bonded glass fibres having a dia, of 2-8 mu and a length of 1/16-1/2" and a coating layer on one or both sides of electrolyte immobilising partially cross-linked polyacrylamide. The total thickness of the separator is 2-7 mils and the thickness of the carrier is 1-3 mils. The separator is of use in a dry cell and does not degrade in the presence of the electrolyte and does not have high electrical resistance.
An adhesive having excellent acid-, water-, and moisture resistance, and suitable for prodn. of glass-mat separator for storage battery is prepd. by copolymerising (a) 15-35 wt. % of alpha,beta-monoethylenically unsatd. carboxylic acid, (b) wt. % of alpha,beta-monoethylenically unsatd. hydroxy ester, (c) 0.5-10 wt. % of unsatd. monoglycidyl cpd., and (d) 40-83.5 wt.% of vinyl monomer other than (a)-(c); blending the resulting copolymer with a liquid medium, and adjusting the pH of the compsn. to 5, using an alkali of b.pt. is not &gt;100 degrees C at normal pressure. Na polyoxhethylene alkylsulphate may be added to the adhesive compsn. The adhesive allows prepn. of glass mat separator having sufficient bulkiness and mechanical strength when used in a storage battery. The glass mat also has sufficient permeability to the electrolytic soln. and gives smaller electric resistance.
A Li-Br cell comprises a solid Li anode, a solid LiBr electrolyte and a bromine cathode operatively contacting the anode so that solid electrolyte is formed at the interface. The cathode may consists of a charge transfer complex of an organic donor, e.g. polyvinylpyridine, and bromine and the anode may have a coating of an organic electron donor, e.g. polyvinylpyridine on its surface. The cathode can alternatively be liq. bromine. The cell is esp. suitable for long life, low current drain applications. The cell has relatively high voltage and energy density and is convenient and economical to produce.
A storage battery has a battery case made of polystyrene/ABS resin blend. The PS/ABS blend resin has high impact strength and excellent oil resistance, and is partic. suitable for use in a car battery. The ABS resin used is obtd. by graft polymerisation of acrylonitrile and styrene to polybutadiene, and is present in amts. of 3-20% in the blend.
An improved silver oxide battery having a high discharge capacitance and of high stability w.r.t time, comprises a cathode, an anode, a separator placed between the anode and the cathode and an electrolyte. The separator comprises composite films consisting of a porous synthetic resin film, such as a polypropylene film, formed on the cathode, an alkali-proof electrolyte preserving film formed on the anode and a cellophane film formed between the synthetic resin film and the electrolyte preserving film. The porous polypropylene film has a high alkali-proof property, a high mechanical strength, a thickness of &lt;50 mu and holes of an average diameter. The cellophane film prevents migration of Ag(OH)2- ions from the cathode side to the anode side. The cellophane film has a high stability in the alkali electrolyte and light mechanical strength.
Excessive discharge of an accumulator and the level of its electrolyte are monitored by a device having a float with a permanent magnet or magnetic material, a case to take the float and with a hole through which the electrolyte flows, a device on the case to suck the electrolyte through that hole, and a magnetic sensor which is activated according to movement of the magnet. Simple construction is provided, with accurate and automatic operation; can be linked to remote controls.
Separator for an alkaline accumulator with a negative electrode made from zinc is improved in that it contains fine particles of a rare earth metal hydroxide (pref. cerium or yttrium hydroxile) in a dimensionally stable, inert matrix (pref. a dried PTFE emulsion or a polyolefin). The separator is porous; the porosity is pref. 50%; the average pore dia. is &lt;200 k. Zinc ions cannot pass through this separator, whereby the spontaneous dissolution of the zinc electrode is suppressed. The prodn. is simple as the separator is shaped by extrusion; it forms a 0.25mm thick foil.
Liquid-tight metallic lead-in for electric accumulators is provided in the scaling region with a coating which contains a resin having carboxy functions. Pref. the coating consists of colophonium, and esp. a mixt. of colophonium with polyvinyl acetate or polyisobutylene. Pref the resin is supplied in the form of a soln. in ethyl alcohol, toluene or trichlocoethylene using either a brush or spray. The soln pref. contains between 2 and 20 wt.% esp. 5 and 7.5 wt.% of colophonium. The coating is pref applied to a thickness of 3 mu to 8 mu. The liquid-tight seal is reliable and lasting and can be applied by automatically working machines. The resins have a strong affinity for housing made from polyolefines.
In a mfr. of flat, multicell batteries of the type used in 'Polaroid' (RTM) cameras in which a base electrically conductive plastics sheet is provided with metal strips, the strips are chemically etched to form discrete portions upon which subsequent components can be applied and at least one continuous strip of metal is left after the etching. Etching to form discrete sections facilitates subsequent subdivision of the sheet into single units and the continuous metal strip acts as a tension rail by which the sheet can be fed through the various processing stations.
A battery jar comprises an elongated casing of plastic material having transverse, pressure-supporting ribs around the periphery, the ribs being fixed by supports around the periphery of the casing, or being integral with the side walls so as to permit elongation of the casing as the battery plates grow with age. This economical, lighter weight battery jar is for heavy duty batteries.
An electrode plate for alkaline storage battery having good adhesion of active materials, low electric resistance and good operating efficiency, is prepd. from a mixt. of an active material powder, thermoplastic resin powder and a solvent which is non-soluble for the thermoplastic resin powder, which is coated on a metal core. The coated metal core is formed by press. and heating to the moulding temp. of the thermoplastic resin.
In a galvanic cell with a light metal, pref. Li negative electrode, a non-aq. electrolyte and a positive electrode, the improvement comprises the use of heavy metal silicates or aluminates as electrochemically reducible component of the positive electrode compsn. The pref. cpds. are Ag2SiO3, PbSiO3, CuSiO3 and CuAl2O4, Ag2SiO3 being esp. suitable because of its high energy density. The positive compsn. is insol. in the electrolyte and is utilised extensively in the current-yielding reaction, so that the high energy density cells have as constant a voltage as possible through the entire discharge period.
A seal is formed between a battery terminal bushing and a plastic lid by covering the bushing with a polymer powder blend, baking for 2-10 mins. at 190-230 degrees C to form a continuous coating, cooling and moulding plastic about the bushing to form a battery lid. The powder blend comprises 25-100 pts. wt. polypropylene or polypropylene-polyethylene copolymer and 75-10 pts. wt. of a polycarbonamide which is compatible with the polyolefin and has a particle size less than 250 mu. The polyamide must have an av. of is not &lt;10C atoms between amide gps.    USES/ADVANTAGES -   Prevents liq. and vapour transmission by a wicking action through the seal between a lead bushing and a battery lid and consequent corrosion about the battery terminals.
A microporous material is made by applying a homogeneous solution containing resin, solvent and non-solvent to a plastic net produced by biaxially stretching an embossed plastic sheet, and drying the net or immersing it in a non-solvent.    USE -   The microporous sheet is suitable for filter material, battery separator, separator for electrolysis cells, etc.    ADVANTAGES -   In comparison with conventional base materials such as Saran screen and non-woven fabrics, the plastic net used here provides following advantages: (i) the net is available in a form of continuous web of high dimensional stability, permitting the process to be operated continuously at high speed; (ii) the intersections of the net are thicker than the other areas, facilitating liquid flow.
Alk- earth carbonates are used as electrolytic redn. solns. in producing electrodes for alk. storage batteries. Use of these carbonate solns. gives product of equal quality from batch to batch as compared with the conventional KOH treatment. In an example, carbonyl Ni powder, CM-cellulose, and H2O were mixed, kneaded and the mixt. was applied to a porous Ni plate. The plate was dried and sintered at 700-900 degrees in H for 10-20 min. The sintered plate was dipped in a CdNO3 soln. at 60-80 degrees for 1-2 min. The Cd-impregnated plate was cathode-electrolysed at 60 degrees and 10-20A/dm2 for 15 min. in a soln. contg. 127g. CaCO3/l. H2O. The treated plate was washed and dried at 105-120 degrees. The impregnation, electrolysis, washing and drying process was repeated 4-7 times to impregnate a desired amt. of the Cd(OH)2 cathode active material to the plate.
Batteries contain porous air electrodes, Zn electrodes, alkaline electrolytes and electrolyte-regenerating agents (synthesised from Ca salts and alkalis) contg. an alkali-resistant binder. The electrolyte-regenerating agent does not disintegrate in the electrolyte, hence it gives long life to the battery. In an example, 7kg. CaCl2 was dissolved in 10l. H2O and to this was added 10l. of a soln. contg. 5kg. NaOH. An alkali-resistant binder such as CM cellulose was added to the pptd. Ca(OH)2 (dia. 0.2-5 mu) and the mixt. was added to the NaOH electrolyte of a battery contg. air and Zn electrodes.
Zn powder, a thickening agent ne.g. CM cellulose), and a mixt. of H2O and H2O-miscible, volatile solvents which do not dissolve the thickening agent are mixed and pressed into an anode. An alkaline prim. battery with this anode has longer life than that with a conventional Zn anode. In an example, 5kg. Zn powder and 100g. CM cellulose were mixed with a mixt. contg. 50 H2O and 20C ml. EtOH, and the mixt. was pressed into anodes.
A web formed from chemically resistant fibres is immersed in a mixt. contg. a resin resistant to an electrolyte for bonding the web and partially coating the fibres with the resin, then the bonded web is immersed in an aq. mixt. contg. a metal salt for swelling or partially dissolving the resin, and the resulting web is treated with a nonsolvent for the resin for removal of the metal salt from the web to impart nontransparent porous structure to the resin layer giving nonwoven fabrics for alkaline batteries. In an example, a blend of polypropylene fibres (2 denier/filament; length 51 mm and 3 denier/filament; length 51 mm) at 50:50 ratio was carded and the web formed was immersed in an emulsion contg. To resin DA 15 (nylon 8) to 27% pickup and dried.    The bonded fabric was immersed in an aq. mixt. contg. 50% ZnCl2 at 55 degrees and subsequently in H2O, washed, and passed between heated rolls to give 0.25-mm nonwoven fabric with liq. transmission 60 mm/30 min. and liq. absorption ratio 310%, compared with &gt;30 mm/30 min. and 260% for a nylon nonwoven fabric. Acylonitrole-vinyl chloride copolymer fibres were also used.
An envelope acting as a separator for accumulator plates, consists of two separator walls fixed at a certain distance by at least one piece of expanded material. An extruder is used to extrude the expanded material into the gap between walls and a template is used to fix the sheet comprising the separator onto a gauge to maintain the two sides of the sheet opposite each other and spaced apart, and the expanded material is then allowed to harden.    ADVANTAGE -   When the plates of the accumulator and esp. the negative plates expand during discharge the internal forces deforming the envelope are distributed in the flat wall of teh envelope rather than concentrated at a region around the edge of the plate. The expanded material is an integral part of the structure and acts as a sealant and an adhesive not requiring to be pressed.
Pressed, porous Zn electrodes are activated with an electrolyte contg. Zn2+, complex ions, or a metal whose electropotential is higher than that of Zn and whose H overvoltage is high enough to avoid self-discharge at the equiv. potential of Zn. This treatment activates the electrode evenly and does not generate excessive H. In an example, ZnO 150 and CaOH 50 g. were mixed with 100 g. 2% PVA. The mixt. was applied to both sides of a wire screen (30 mesh, 90 x 90 mm.) and the electrode was activated in a PbO-satd. 15% KOH electrolyte. The electrode showed higher rechargeability than that activated in a conventional 15% KOH electrolyte.
A conveyor carries individual thermoplastics sheet along a path from a loading station of a transfer station. At the transfer station one of a number of relatively flat pick up arms, having vacuum apertures in their lower surfaces, picks up one of the sheets and transfers it, during rotation of a turntable carrying the pick-up arms, to a sealing station. During movement of the sheet from the transfer station to the sealing station an elliptically shaped curved rod engages the sheet of fold it into an envelope about the arm to be presented in sealing relation to the sealing device. Apparatus is simple in operation and easy to maintain.
A high performance electric power battery comprises 1 pair of electrodes, a polypropylene insulator, and insulating oil consisting of a phosphate ester or a mixture of phosphate ester and an aromatic hydrogen carbide cpd. and additive of 0.1 to 10.0% of radical capture agent.
A HgO-coated Zn plate or foil is used as anode for primary alk. battery. The HgO coating on Zn plate or foil improves amalgamation of Zn, and provides batteries with good discharging characteristics. In an example, thin Zn plates (&lt;0.2 mm) were coated with a mixt. contg. HgO 100, CM-cellulose 5g, and H2O 20 ml, dried, and laminated to obtain a Zn anode. An alk. battery made with this anode had discharging time 15-26 min at -10 degrees and 60 omega until its voltage dropped to 1.0 V, as compared to 2-5 min for a battery made with a conventionally amalgamated Zn anode.
In a flat primary battery structure, comprising sheet type separators between electrochemically active battery sheet elements, comprising anode and cathode materials and electrolyte combined with sheet type conductive inter cell connectors and oppositely disposed sheet type current collectors, forming a series connected multicell structure with seals surrounding the active elements between the peripheries of the inter cell connectors and contiguous portions of the separators, the overall peripheral dimensions of the separators exceed the overall peripheral dimensions of the connectors and active elements, and the peripheral dimensions of the inter cell connectors exceed the peripheral dimensions of the active elements, so that the peripheral portions of the separators extend beyond all the peripheral portion of the active elements and inter cell connectors sealed thereto. Batteries for use in a self-developing film pack. Overall efficiency of assembly is improved, esp. as regards heat sealing, to obtain maximum efficiency of the separator during and after assembly. Maximises production of batteries having acceptable performance.
A cross linking agent and an organic solvent are added to thermoplastic rubber consisting of polystyrene-polybutadiene-polystyrene or polystyrene-polyisoprene-polystyrene to make a soln. and portions of the cell to be sealed are coated with the soln. and dried. Seal obtd. has good liquid leakage resistance.
The separator for a dry cell is produced by mixing a paste material and an electrolyte with an org. soln. of a modified vinyl acetate resin and coating e.g. Kraft paper with the mixture to obtain a separator for dry cells. Dry cells with good discharge performances are obtained.
0.3-2.0 wt % of granulating assistant of acrylic acid system water soluble compound is added to a mixt. of a depolarizer and a conductive auxiliary agent e.g. acetylene black. The mixture is made into granules and then they are moulded to a desired shape, thereby obtaining a moulded cathode mixture for alkaline batteries.
A layer-built dry cell comprising zinc anodes having carbon films of 100 to 150 microns at one side, the carbon films consisting of carbon material such as graphite or acetylene black and a binder such as epoxy resin or polyethylene, the zinc anodes connected by the carbon films to cathode mixtures consisting of manganese dioxide and acethylene black, and an electrolyte containing 30 to 40 wt. % of zinc chloride. By use of an electrolyte having the abovementioned concentration of zinc chloride, no pinhole is generated in carbon films in preservation and the sufficient performance of this layer-built dry cell is obtained.
In alk. Zn batteries, dendrite pptn. during charging is prevented by placing the anodes in contact with polycationic cpds. hardly sol. in the electrolytes, and this extends service life of the batteries. In an example, a Ni grid was filled with a paste made from ZnO and 3% poly(vinyl alcohol) soln., dried, and electrolytically reduced in NaOH to obtain a Zn anode. The zn anode was dipped in aq. 20% poly(N,N-dimethyldiallylammonium chloride) soln., dried, and assembled with a NiO cathode and 10N NaOH electrolyte to obtain a sec. battery.
A car battery connector lead has a connector socket which fits over the terminal pillar of the battery and which is encased in a synthetic resin sheath, only the inner surface of the socket being uncovered. The sheath extends over the end of the lead in the region where the lead is connected to the socket, and is also provided with a damping formation so that the socket can be tightened on the pillar. Corrosion of the socket is reduced.
In a galvanic cell with a light metal, esp. Li, negative electrode, non-aq. electrolyte and a positive electrode, the electrochemically reducible constituent of the positive electrode compsn. consists of Bi2O3 and the electrolyte consists of a soln. of a conducting salt, pref. 1 M LiClO4, in a mixt. of (CH2)3CO3 and MeO. CH2CH2. OMe, pref. in 40:60 vol. ratio. The positive electrode compsn. can also contain 5-30, pref. 15 wt. % Sb2O3 or 0.5-5, pref. 1-5 wt. % finely-divided Bi. The cell has very constant potential (of 1.5V), is interchangeable with other cells (Leclanche cells) and can operate in a wide temp. range with high discharge current densities. It has very good storage characteristics and its energy density is 4-5 times that of Leclanche cells.
In a galvanic cell with a light metal, pref. Li, negative electrode, a non-aq. electrolyte and a positive electrode, the electrochemically constituent of the positive electrode compsn. consists of Sb oxide, pref. SbO2. The electrolyte pref. is a 1.2 M soln. of LiC104 in a mixt. of butyrolactone and MeO. CH2CH2. OMe in 40:60 vol. ratio or of (CH2)3CO3, MeO. CH2CH2. OMe and tetrahydrofuran in 30:35:35 vol. ratio. The system has good storage characteristics, high energy density wrt. vol. and interchangeability with Leclanche cells.
In a galvanic cell with a light metal, pref. Li, negative electrode, a non-aq. electrolyte and a positive electrodE, the electrochemically reducible constituent of the positive electrode compsn. consists of arsenites, of Ag or Ho. The electrolyte pref. is a 1.2M soln. of LiC104 in a mixt. of (CH2)3CO3, tetrahydeofuran and MeO, CH2CH2OMe in 30:35:35 vol. ratio of (CH2)3CO3 and MeO. CH2CH2. OMe in 1:1 vol. ratio. The system has a high energy density and discharge potential, max (95%) utilisation of active compsn. and very constant potential throughout discharge.
A multicell battery comprises (a) a stack of individually sealed liq. electrolyte contg. cells (b) inter cell connections between cells and end terminals on the end cells, (c) an insulating, moisture-proof, performed plastic container contg. the stack and slightly larger than it, (d) an encapsulating material filling the free space between stack and container, enclosing each cell of the stack and electrically isolating them from the container and each other except for the electrical inter-connections, (e) a metal can having one open end surrounding the container and (f) an end cell closure for the open end of the can. The plastic cup prevents egrees of cell electrolyte and entry of moisture into the encapsulating material under severe thermal cycling e.g. a stack without the plastic container tolerated cycling from -60 degrees to +175 degrees F for 14 days while a stack with the plastic container withstood leakage for over 28 days.
The proposed treatment, for prepg. separators for lead accumulators from emulsion polymerised PVC (and hence contng. alkylarylsulphonate surfactants), is carried out for 15-30 mins. at room temp. in satd. Ba(OH)2 giving increased capacity. The negative electrodes contain an organic expander, namely humic acid, or sulphonated beta-naphthol+dihydroxyphenylsulphone condensation product, or crystalline phenol+beta-naphtholsulphonate+HCHO condensate. The presence of sulphanol has an adverse effect on effectivity of wetting agents added after fusing PVC separator.
Azo compds. RN:NR'(R = naphthyl with OH and/or SO3Na substituents, R' = group contg. substd. azobenzene residues) are added to alkali electrolytes of Zn battery an Zn anti-corrosive agents. The inhibited corrosion of Zn prevents gas formation in the battery and increases its discharge capacity. In an example, a mixt. of MnO2 and graphite was wetted with KOH, kneaded, and pressed into a cylinder in a cathode casing. A separator was placed in the cathode centre and the remaining space was filled with an anode paste of Zn powder treated with a mixt. of 30% KOH, 0.05% Sudan III in xylene, and CM cellulose. The sealed battery had better discharge characteristics than a conventional one not contg. Sudan III.
An electric storage battery has a casing of hard rubber or resin-bonded rubber, and carrying handles each formed of a flexible band passing through casing flange holes each reinforced by an insert embedded in the flange during moulding. The bands are pref. of polypropylene rope and each insert is a sleeve surrounding a band and from which flanges project to spread the load. Inserts are e.g. of antimony, lead or phenolic plastics.
Pole piece for lead accumulators employed to drive electric vehicles, the novelty being that where the piece passes through the casing it has an external thread and is sealed w.r.t. the electrolyte, on the cover, by a plastic nut and an O-ring, the pole piece contg. a cast -in bush linked mechanically and electrically to a flexible cable; the surface of the pole piece and the nut are covered by a hood contg. an outlet for the cable, the hood being filled with an insulant. The cast-in bush is pref. linked by a conductor to a contact projecting beyond the insulant, and a crimped joint is pref. employed between the bush and the cable; the insulant in the hood is pref. polyurethane. A reliable joint, protected against short circuits, but with a contact permitting the testing of the cell.
A carbonaceous material suitable for use in the electrocatalytic substrate of a fuel cell electrode is prepd. by (a) depositing a copolymer contg. at least 85 wt. % vinylidene chloride, balance one or more compatible vinyl monomers from soln. onto C particles having an average particle dia. of 0.07 u-130 angstroms and a pore size of 30-300 angstroms such that the copolymer contributes 1-15% of the total C content of the particle-copolymer mixt. and (b) heating to 700-1400 degrees C to pyrolyse the polymer and generate a porous C char. The electrode is useful in fuel cells having liq. electrolyte and gaseous reactants and operated at ambient temps. Polarisation voltage loss at the air electrode may be reduced for 30-50% at current densities of 50-800 mA/cm2 compared with polarisation of C black material of similar particle size and is only about 1/4 that of polyvinylidene chloride char alone.
An electrochemical cell comprises (a) a conductive can having one open and one closed end, acting as first terminal, (b) an anode layer within and in surface contact with the can, (c) a porous separator within and in surface contact with the anode, (d) an elastically deformable carbonaceous slotted annular bobbin as cathode collector within and in surface contact with the separator and biased against the separator to maintain good physical contact between collector, separator and anode during discharge, (e) an active reducible cathode soln. within and through the collector and separator, (f) a can cover serving as second cell terminal, (g) an insulator sealing the cover to the can and (h) a conductor contacting cathode collector and can cover. The cell may use highly active material for long service life, and is easily assembled in cylindrical form with low internal resistance maintained throughout, e.g. an Li/2M eutectic LiAlCl4-SO2Cl2 cell had open circuit voltage of 4.00V, initial and final impedance of 3.02 and 2.89 omega, average voltage on discharge through 42.7 omega of 3.25V and discharge capacity of 6.49 A-hr.
The binder for Pb accumulator plates consists of chopped fibrous matl. e.g., chlorinated PVC which is twisted with 1-3% lubricant soln. and rewound with a 5-50% ditto, and inserted as thread with 40-100 twists of elementary fibres. Use of lower percentages of lubricant in the two operations eliminates inter-fibre adhesion which caused uneven distribution, and hence reduced strengthening and holding sought, as well as cutting electrical conductivity.
The separator of a dry cell consists essentially of insoluble and inert synthetic fibril sheet. The sheet absorbs an electrolyte in a max. amt of 200 wt. % to the separator. Synthetic resins, such as polyethylene, polypropylene, polystyrene, polyphenylene, polyphenyleneoxide, polyester, polyacrylnitrile, polyamide or the like, are mixed with inorganic fine particles to form a mixture. The fibrils are made from the mixt. The separator has a high mechanical strength, stability and absorbing power.
The sealed storage battery comprises a cathode, an anode, an electrolyte and the separator placed between the anodeaand, the cathode. The separator comprises a sheet consisting of glass fibres having average fibre diameter of 0.5 mu-50 mu and synthetic resin fibres, such as popypropylene fibres of 2.5 mu diameter or polyester fibres of 4.0 mu diameter. The separator has a high mechanical strength. It absorbs the electrolyte fully more than conventional separators. It has a long life time. The sheet is bonded with a bonding agent of gelatin or acrylic acid emulsion.
Polysaccharide ethers from plant viscous substances are excellent electrolyte-gelling agents for dry-cell batteries. The use of such agents increases the battery life. In an example locust bean gum was treated with propylene oxide to obtain a product havin 0.1-0.3 mole % of etherrized fraction. etOH 40; cross-linked starch 10; cross-linked etherized starch 30; etherized locust bean prepn. 20; and H2O 10 parts were mixed. The mixt. was used to produce a battery which was kept at 50% relative humidity and 45 degrees for 12 months. The resp. discharge lives for new and conventional batteries when discharged to 0.9 V over a 4-omega load were 620 and 450 min.
A process for preparing microporous aromatic polysulphone webs, suitable for battery and/or fuel cell membranes, comprises (1) continuously coating a moving carrier belt with a paste consisting of a solvent and a solid, 80 wt. pt. of the solid being an aromatic polysulphone of formula I (where R is C(CH3)2 or SO2) and is not &gt;20 wt. pt. of the solid being inorganic filler; (2) contacting the coated carrier belt with a liquid coagulant miscible with the solvent to coagulate I; (3) stripping the microporous fulm from the carrier belt; (4) removing residual solvent and coagulant opt. by washing with a suitable solvent and, (5) drying at raised temp. to removal liquid components. The membrane has good mechanical and electrical properties, uniform pore distribution, low water permeability and low breakdown resistance.
Zinc electrodes for batteries are prepd. by adding foaming agent to polyvinyl alcohol soln., in 1:100 ratio and then mixing the resulting foam with Zn dust and ZnO; after partial drying 1 mm and 2 mm fractions are sepd. and the granulated prod. press-moulded and dried to give highly porous and mechanically strong electrode.
The electrophoretic deposition for obtg. cadmium electrodes for alkaline accumulators e.g. from a suspension of CdO in a carbomethyoxycellulose suspension, is followed by pressing at 300-450 kg/cm2 then heating at 180-250 degrees C/1-3 hrs., and finally pressing at 600-800 kg/cm2. The resultant electrode has better electrical props. than one made just by electrodeposition, and mfg. time is decreased.
The process comprises reacting polyamide woven cloth with paraformaldehyde to change its active gp. to a methoxymethyl gp., and coating the methylation polyamide woven cloth with PVA.
The persulphate storage battery has a cathode activator comprising mixt. of a soluble persulphate fine particles and soluble persulphate particles having larger particle size than the insoluble persulphate particles. The insoluble particles, such as kalium persulphate, and the particles, such as sodium persulphate or ammonium persulphate, are mixed with graphite conducting agent and a polystyrene binder. The mixt. is pressed to form a cathode plate. Anode consists of Zn, Al or Mg. Electrolyte consists of (sea)water. The storage battery is rapidly activated when the electrolyte is poured in the battery. It has a plane working voltage and it has improved discharge efficiency.
Powd. ZN is mixed with a thickening agent and NH4OH, and the resulting paste is applied to alkali-resistant metal plates and dried to obtain high-strength Zn anodes. In an example, powd. Zn 325, ZnO 150 and methylcellulose 22 g. were mixed for 3 hr. prior to addn. of 300 ml. dil. NH4OH. After standing for 5 hr. the paste was applied to a Ni grid and dried to obtain a Zn anode. A Ni-Zn battery contg. this anode had discharging capacity 300 mA-hr. even after 50 charging-discharging cycles, compared to 50 mA-hr. for that contg. conventional Zn anode.
A Zn anode of a larger vol. than that of the cathode is attached with an amalgamated Cd electrode for O absorption. Use of such a Zn anode increases battery life. In an example, a paste contg. Zno, short synthetic fibre, and Cm cellulose was applied to the major portion of a Cu net and a paste mixt. contg. CdO, short synthetic fibre, HgO, ethylene glycol, and poly(vinyl alc.) was applied to the remaining portion of the Cu net. The electrode was dried and treated with KOH to obtain a Zn anode with O absorption electrode. A battery assembled with the anode had improved charge and discharged capacity as compared with a conventional battery.
Gel-form Zn anodes for alk. batteries are prepd. by wetting powd. Zn with H2O, mixing with alkali-resistant paste contg. ZnO or Sn(OH)2, and adding alk. electrolyte. The use of such Zn anodes improves discharge characteristics and storing stability of alk batteries. In an example 1000 g. of powd. amalgamated Zn were wetted with H2O and mixed with a mixt. contg. powd. ZnO 70 and carboxyvinyl polymer 10 g. After agitating for 10 min., 60% of 36% NaOH was added to form the anode. An alk. battery made with this anode had 30.5 hr. service life when continuously discharged at 20 degrees through 500-omega resistance until the emf. dropped to 0.9V. In contrast, a conventional alk. battery had 25.8 hr. service life. The battery also had a good storing stability.
A storage battery has a battery casing with its interior divided into cells by partition walls of thermoplastics material with metal conducting members connecting the pole bridges of adjacent cells, passing through recesses in the partition walls. Each conducting member is sealingly surrounded by an inter. panel of thermoplastics material, the inter. panel being located in the recess in the partition wall so that there is a channel defined between the edge of the panel and the edge of the recess with the panel sealed by a molten thermoplastics sealant introduced into the channel and allowed to solidify. The inter cell connections are arranged so that the seepage of electrolyte between adjacent cells is substantially eliminated.
Galvanic Li-I2 cell with a Li lining forming the anode and a cathode, inside this, of an organic charge transfer complex cpd. and I2, has a cathode with a current collector connected to a lead with an insulating coating passing through a duct in the Li lining and a LiI electrolyte layer between the lining and the cathode, which has the same extent as the inner area of the lining and/or the outer area of the cathode. Used in implanted prostheses, e.g. cardiac pacemakers. Only min. amts. of plastics are used, enabling the overall dimensions of the cell to be reduced or more active constituents to be used. Since there are no air or empty spaces, a larger contact area between the anode and electrolyte is obtd.
Accumulators incorporating gps. of alternating positive and negative electrode plates where the plates are clad in sleeves to prevent dendritic short circuiting, the sleeves being perforated near the base to allow the plates to be anchored by a resin cement to teh base of the accumulator casing. The cement is deep enough to seal the holes in the base of the sleeves. For mfr. of accumulators of the 'filled for life' pattern, not requiring periodic replenishment of electrolyte. The anchored plates resist displacement or damage due to vibration or knocks in arduous conditions.
A button type alkaline cell is made by applying polyisobutylene having a mol. wt. of 2000-10,000 to a contacting part between a sealing plate and a sealing packing integrating the sealing plate with the sealing member. By applying the polyisobutylene layer, the sealing plate can be sealed to the sealing packing hermetically.
A paste-like mixt. consisting of metal powders, a binder, and an appropriate solvent is coated on belt-like perforated metal sheet or metal screen. The coated metal sheet is dried, compressed, and sintered to give a battery electrode support. The obtd. electrode support has uniform thickness and porosity. In an example, Nicarbonyl powder 50-150 was dispersed in a methylcellulose 3-H2O 100 parts mixt., a Ni screen belt was passed continuously through the dispersion, thickness of the dispersion coated on the belt being adjusted by blades. The belt was dried, passed through a pair of rollers to readjust the coating thickness, and sintered at 800-900 degrees in inerg gas (H, N, NH3, etc.) to give Ni-electrode substrate sheet. The Ni(OH)2 electrode active mass was impregnated on the sintered Ni sheet and the obtd. electrode was used in Cd-Ni storage batteries. The lot-to-lot fluctuation in the battery capacitance was very small.
An accumulator with a Zn cathode and its separator prepd. by dissolving (a) polyvinyl alcohol in water, adding an aldehyde to convert the alcohol to acetal, an acidifying cpd., and an anti-oxidant the wt. of which is 0.5-2% of that of the polyvinyl alcohol, (b) pouring the soln. onto rigid plates and leaving to dry, (c) heating the membrane obtd. in a non-oxidising atmos. at 120-250 degrees C and (d) impregnating the membrane with water, as in parent patent, is added at stage (a) in an amt. 1-5, pref. 3% of NaSO4 is added at stage (a) in an amt. 1-5, pref. 3% of the wt. of polyvinyl alcohol. The sulphate increases the life of the separator. The separator has low electrical resistance and shows excellent selectivity w.r.t. zincate.
A Cd-Ni cell and its separator prepd. by (A) dissolving polyvinyl alcohol in crater adding an aldehyde to transform the alcohol to acetal, an acidifying cpd. and an anti-oxidant, the wt. of which is 0.5-2% of that of the polyvinyl alcohol, (B) forming a membrane with soln. from (A) and allowing to dry, (C) heating the membrane in a non-oxidising atmos. at 120-250 degrees C and (D) impregnating the membrane with water, as in parent patent, is improved in that an alkali sulphate esp. NaSO4 is incorporated in stage (A) in an amt. 1-5, pref. 3% of the wt. of polyvinyl alcohol. The sulphate increases the life of the separator. The cell is a reversible electrochemical generator and the separator has excellent selectivity w.r.t. O2 and low electrical resistance.
A method of assembling a storage battery ulitises vibratory energy to friction weld the cover to the casing. Both casing and cover are of thermoplastic matl. The mating surfaces of casing and cover fuse under the friction caused by the vibrations so forming a sealed joint. An improved bond between cover and casing is formed with reduced flash in a shorter time than obtainable from prior methods.
A lithium-iodine cell enclosure comprises a first hollow casing of matl. non-reactive with iodine, having an opening at one end closed by a sealed closure of matl. which is non-reactive with iodine, a second hollow casing enclosing the first casing and having an opening at one end closed by a sealed closure, the closure of the first casing being adjacent the end of the second casing opposite to the closure of the second casing, the first and second casing being of the same shape and fitting closely together, and a third hollow casing enclosing the second casing and having an opening at one end by a hermetically sealed lid, a space being provided between the second casing and the lid of the third casing. For batteries of implanted cardiac pacemakers. The enclosure minimises risk of iodine or gas leakage, is easy and economical to mfr., and has a long wear life.
Both surfaces of a cellophane sheet are coated with a paste mixt. composed of magnesium oxide, a gelling agent for electrolyte and a binder, thereby making a separator for alkaline batteries. Alkaline batteries with increased storage and discharge performances can be obtd.
One or both surfaces of a non-woven cloth or cloth of alkali resisting synthetic fibre is coated with a mixt. composed of MgO, a gelling agent and a binder, thereby obtaining a separator for alkaline batteries. Alkaline batteries with increased storage and discharge performances can be obtd.
An alkaline storage battery comprises an anode, a cathode, an alkaline electrolyte and a separator placed between the anode and the cathode. The separator comprises an alkali proof porous sheet impregnated with a mixt. of B2O3 or a B cpd, an alkali proof gelatinizing agent and polyvinyl alcohol, and fluorocarbon resin thin films containing alkali insoluble metal oxides coated on the both surfaces of the alkali proof porous sheet. The separator placed between the cathode and the anode is water un-soluble and hydrophilic. It has a high mechanical strength and a low electric resistance. The fluorocarbon resin thin films prevent the short circuit between the cathode and the anode perfectly. It has a high mechanical strength and a low electric resistance.
The alkaline storage battery comprises an anode, a cathode of nickel oxide (NiO), a separator separating the cathode and the anode and an electrolyte. When the capacitance of anode is 1 Ah, the alkali electrolyte filled in the battery is 0.8ml/Ah to 1.5ml/Ah. The anode comprises a net collector and mixture coated on the net collector. The mixture consists of zinc, zinc oxide (ZnO), bismuth oxide (Bi2O3), calcium hydroxide Ca(OH)2 and polyvinyl alcohol. The life time of cycles of charging and discharging of the battery is improved. The battery is formed with small size. It is used in a Zn-Ni alkaline battery.
The battery has a separator a non-woven fabric consisting of glass fibres and polypropylene fibres. The separator is produced to making a non-woven fabric from a mixt. of glass fibres having a dia. of 1 to 10 mu and polypropylene fibres, and thermally fusing the polypropylene fibres in the non-woven fabric at a temp. near the melting point of the polypropylene fibres. The separator has excellent acid-resistance, liquid-retention property, hydrophilic property and great mechanical strength.
A carbon film is formed on a current collector of a metal strip such as a copper strip by coating the current collector with a mixt. of carbon powder, binder and solvent and heating the mixt. layer at 60-70 degrees C to evaporate the solvent, such as toluene. A flexible carbon thin film with high electric conductivity and a cathode mix. are placed on the carbon film. They are united as one body by pressure. The flexible carbon thin film is fabricated by forming a mixt. of polyisobutylene having a molecular wt. of 105, flaky graphite and acetylene black into a sheet. The cathode mix. consists of 80 pts. of copper chloride, 18 pts. of flaky graphite and 2 pts. of polyvinyl chloride powder. The current collecting effect of the metal current collector and cathode mix is increased. Bad contact due to peeling-off or loosening of the film on the current collector is obviated.
Flat alkaline cells, with at least 2 flat electrodes of opposite polarity and a porous separator impregnated with an alkaline electrolyte between and in contact with these, have the electrodes in a sealed, liquid-impermeable envelope of plastics film with first, second and third connections to wallns) of the envelope, each of these connections having an inner and an outer lead on the inside and outside of the wall over openings in the wall and connected firmly to the wall with a thin layer of an adhesive sealant not wetted by the alkaline electrolyte, the inner and outer leads being interconnected electrically through the openings. The invention is esp. applicable to rechargeable Ni-Cd and Zn/MnO2 cells etc.
Electrochemical generator functioning by the action of melting a saline electrolyte is proposed, and wherein the heat required to melt the electrolyte is transferred via the electrodes that are heated (in)directly by an exothermic pyrotechnical mixt. located on the outer region of the pair of elements or stack of element pairs that are specif. of a AgCl film (foil) and Mg foil (film) combined with an electrolyte that consists of an eutectic contg. a soda and potassium. The electrolyte is specif. contained in a separator made of woven or non-woven PTFE fibres.
Battery cell has positive and negative electrode layers, two plastic films enclosing the cell, and a separator between the electrode layers, the separator being heat sealed to at least one of the plastic films. Ensures that the electrode layers remain apart, even when they are pressed together tightly. The construction enables the cells to be produced simply and automatically. Use of material for the separator is reduced to about half.
A resealable vent for a plastic-cased battery cell comprises a passage in the interior of a hollow pin integrally formed with an projecting inwardly from one case wall and with the inner end bonded to the opposite wall, The passage including an internal opening of reduced cross-section and a seat surrounding the opening, a seal in the passage normally blocking the opening, and biasing normally compressing the seal against the seat. The seal is further compressible against the biasing to unblock the opening and vent gases when the internal pressure rises above a set level. The seal is pref. a neoprene rubber ball with a Shore hardness of 70. The vent is e.g. for a rechargeable flat battery for a miniature calculator.
The battery container of positive electrode contains a positive activator, a separator, an electrolyte impregnating sheet, electrolyte and a negative electrode. The container is sealed with a sealing plate and a packing. The circumference of the electrolyte impregnating sheet is impregnated with a photo-sensitive resin, such as NA or resins having photo-sensitive radicals (diazo radial, azide radical). The impregnated photo-sensitive resin prevents the leakage of the electrolyte.
Appts. for welding together containers, esp. synthetic resin battery casings having perforated covers and pressing devices for the covers, has in the region of the presing device, a pressing/connecting device for pressing into the openings in order to tert the liquid-tightness of the container. The liquid-tightness of the container may be tested directly by the appts., immediately after welding. Provision and operation of a separate testing machine are unnecessary thus reducing costs.
A laminated plate is prepd. by pressing and heating a substrate of polyolefin (deriv) and an unvulcanised rubber sheet consisting of polyolefin (deriv) and contg. unvulcanised rubber, vulcanisation agent, filler and pigment. The plate is used for sealing members in prim. or sec. cells to increase the liq. leakage resistance of the cells.
The battery also contains a pasty aq. soln. of CMC or sodium acrylate contg. water placed on separators exposed to the electrolyte. The water in the electrolyte is lost by oxidization of the nickel of the anode. The storage battery has a high discharge voltage and can be used at high temps.
The anode comprises a sheet consisting of mixt. of the anode activator and alkali proof short fibres. The activator and the short fibres are bonded with each other with a bonding agent comprising aq. suspension of fluorine contg. polymers. In an example 100 g zinc activator, 8 g fluorine contg. polymers, 0.5 g polyamide short fibres and 30 g water are mixed in a mixer. The mixt. is pressed with a roller to form sheets. The sheets are laminated and pressed with the roller to form a sheet of the activator. The activator sheet is stuck on the anode collector to form the anode.
Material is based on a synthetic, hydrophobic base polymer which exhibits, at least in the region of its surface, a cross-linked, polar graft copolymer material, the latter having, in at least the surface region metal atoms of ions which are chemically bound and cannot be removed by dissolution. Suitable metals are Al, Fe, Cr, Ti, Pb, Ni, Zn Ag, Cd alkali metal and/or alkaline earth metals. Pref. the metal atoms or ions are present in a surface region of the graft copolymer which has a thickness of 0.05 to 2 mu m. The material is used in applications where reduced permeability to liquid solvents or gases is necessary; as membrane separators and diaphragms for electrochemical cells fuel cells and electrosynthesis cells.
In filling tubular electrodes with lead bores for lead accumulators by pressing a pasty active compsn. contg. a mixt. of Pb oxides, H2SO4 and H2O into them the Pb oxide slurry also contains fibres of a material resistant to the electrolyte, which partly enter the pores of the walls of the tubes and cover these as liquid passes out. The compsn. pref. comprises 100-600 cm3 H2O and 5-120 cm3 H2SO4 (density 1.4g/cm3) per kg. Pb oxides and also 0.1-2 wt. % fibres w.r.t. Pb oxides. Glass or synthetic (e.g. polyester or polyethylene) fibres can be used. Satisfactory filling is achieved and no large amts. of the compsn. escape through the pores.
Injection moulding of an open topped box shaped container having transverse partitions or partitioning ribs joined to the bottom wall, is done with a mould which has four laterally movable side walls to enclose the mould cavity in conjuction with opposed plates carried by movable and fixed platens of the moulding press. Cores are carried cantilever fasion eg. by the fixed plated. The material is injected through a primary inlet sprue, hot runners cold runners and gates positioned at the parting plane adjacent the fixed ends of the cantilevered cores. Used esp. for battery cases. Injection pressure on the cores is balanced thus avoiding distortion and uneven thickness throughout the case. Release and ejection problems are solved. The mould is simple and of economical mfr.
The electrode assembly of a flat alkaline cell, comprising a pair of opposite polarity electrodes with a porous, alkaline electrolyte-contg. separator between and in contact with them, includes an auxiliary electrode. The assembly is enclosed within a sealed, liq. impervious plastic film envelope have three terminal connections to the respective electrodes, the first comprising a current collector adjacent one end of the electrode assembly in contact with one of the pair of electrodes and (partly) exposed through an opening in one wall of the envelope for making an external connection. A layer of adhesive-sealant, nonwettable by the alkaline electrolyte adheres and seals together the current collectro and envelope, at least around the periphery of the opening. The sealant is pref. formulated from fatty polyamides.
In an injection moulding appts. in which an internally partitioned container is moulded between first and second mould halves between which a cavity of the desired shape is defined and one of which carries cores defining the partitions working material is injected into the cavity through gates lying in a plane around the open end of the container. The gates are fed by primary inlet sprues passing through the mould halves, the spures being fed by a single main inlet. In one embodiment the mould includes a female part provided with cores, and in a second embodiment the mould includes a male part provided with cores.
Sealing agent is filled between the battery case which contains the electric generating element of the battery (e.g. a silver battery, nickel-zinc battery, alkali-mangane battery, etc.) and a gasket, between the end plate and the gasket, or between the current collector and the gasket. The sealing agent is a homopolymer or copolymer having monomer unit of formula (I) (where Rf is linear or branced 3-21C perfloroalkyl; R is H or methyl): As the sealing agent possesses a perfluoralkyl group and hydroxy group at lateral chain terminal positions, ti has strong water repellency, permitting a sealed film to be formed on the surface of the battery case, end plate, or the current collector.
Improved separator for use in a storage battery containing an alkaline electrolyte, a positive electrode of nickel oxide and a negative electrode of Cd. The separator uses adhesive polyolefin fibres having different melting points which are woven to form polyolefin sheet, several of which are laminated. The laminated sheets are then pressed and heated to form the separator. The polyolefin fibre separator has a high water permeability and preserves the electrolyte.
Voltaic cell has a negative elctrode (Ie of light metal or Zn, an electrolyte, and a positive electrode (II). The novelty is that electrode(II) is an insol. polyelectrolyte, the solid ions or gegenions of which are electrochemically reducible. The polyelectrolyte may be anionic or cationic, the anionic polyelectrolyte pref. consisting of resins which form complexes with the gegenions, the genenions being reducible metal ions. The reducible part of electrode(II) is pref. a polymer of (all wt. %) 95% acrylic acid and 5% ethylenedimethylacrylate, all the H ions being replaced by Cu ions. Electrode (II) pref. also contains 8-12% graphite and 1-10 % PTFE. Electrode (I) is pref. Li, and the electrolyte is pref. (A) a 1 molar soln. of LiClO4 in a mixt. of 40 vol % propylene carbonate (PLC) and 60 vol% 1,2-dimethyoxyethane (DME); or (B) a 1 molar soln. of LiClO4 in a mixt. of 30 vol. % PLC, 35 vol. % DME, and 35 vol. % tetrahydrofuran. Used for Li batteries with a very long shelf life.
Primary cell with negative zinc electrode (I) and positive AgO electrode (II), with an alkali electrolyte, where the surface of the AgO is reduced so the cell has the discharge voltage of the Ag2O/zn system. The AgO is sepd. from the positive terminal by a non-conducting layer of plastic, and contact is achieved by a layer of porous silver facing electrode (I) and located above a porous layer of Ag2O connecting the Ag with the AgO, whereas a metal contact is used between the layer of porous silver and the positive terminal. The plastic layer is pref. PTFE, and the metal contact is pref. silver, alternative cell designs being included in the claims. High voltage stability during discharge; very low self discharge giving long shelf-life; simple to mfr. with consistent properties; and can give pulsed load of up to 80 mA suitable for operating watches using luminescent diode display.
The prodn. of an Fe electrode for alkali accumulators by applying active material to a metal tape mesh comprises adding an aq. soln. of 3-20 wt pts. surfactant (w.r.t. the dry wt. of the active material) to the active material contg. magnetite ore concentrate, Fe2O3, synthetic fibre, industrial FeS and aq. NiSO4 soln. applying to a steel tape mesh, drying 5-10 min. at 150-300 degrees C, treating the resultant electrode with a binder, consisting of 15-20% LiOH suspension in a 20% epoxide resin soln. contg. a hardener, e.g. polyethylenepolyamine, and then drying the electrode for 10-30 min. at 70-160 degrees C. The electrode has better electrical and strength characteristics than the usual lamellar Fe electrodes.
Moulding battery boxes with integral internal partitions using a mould which is ribbed opposite the roots of the cavities for the partitions. the moulding material is injected via holes aligned with the ribs. The width of the ribs is slightly greater than the crests of the moulded partitions, allowing the partitions to be nested into the grooves in the base of a box stacked on top. Esp. for injection moulding automobile battery bodies of e.g. polypropylene. The ribs and the injection nozzle profiles keep the melt thickness approximately constant across the base of the box, compensating for the extra material at the root of the partitions. The ribs act as baffles to inhibit lateral flow to adjacent partitions from injection points which may be fed more rapidly than adjacent points, e.g. due to temperature variations.
A hermetically sealed Ni-H secondary cell comprises (a) a cell component stack of flat annular elements, all having equal inner and outer dias. and a common annulus axis, comprising a hydrophilic positive electrode, a hydrophilic separator, a negative electrode, a hydrophilic electrolyte reservoir and a gas flow space; (b) a hydrophobic annular cell case of rectangular cross-section enclosing the stack and providing a cell mainfold vol.; (c) a hermitically sealed press. vessel contg. the cell case and providing an axial reactant gas storage vol. within the inner circumference of the cell case annulus; (d) a communication port inside the circumference of the cell case annulus, with a hydrophobic gas permeable Teflon (RTM) membrane sealing it; (e) aq. KOH electrolyte in the cell case; (f) H2 reactant gas within the press. vessel, and (h) separate electrical connections from positive and negative electrodes to the outside of the press. vessel. Provides compact cell with good heat transfer and min. passive surfaces for electrolyte loss.
Productivity is improved by providing the line with a horizontal compensator with which sensors in weighted loops interact and are electrically connected to a device for controlling the speed of the crosswise cutter drive mechanism. The compensator is a vessel, the top side of which forms the lower arm of the conveyor in the sintering machine, and the bottom side is in the base of the machine. The sensors consist of vertically distributed balanced probes which can be rotated on a spindle supported by a plate which sends a signal to the main control mechanism.
Catalyst plug for a battery, which causes the reaction between oxygen and hydrogen produced during charging and discharging of the battery to return to water, has a catalyst carrier such as powdery or granular carbon black is impregnated with Pd or Pt chloride catalyst soln. The carrier with the catalyst is then reduced, and the carrier subjected to water repellent treatment with fluorine system resin. The catalyst carrier is sintered to form a catalyst block which is placed in a container to complete a catalyst plug for a battery.
An alkali-resistant porous metal foil is coated with Ni powder, the foil is sintered at 900-1200 degrees in inert or reducing gas to form sintered Ni layer and the Ni layer is coated with Cd contg. paste to give a paste-type Cd electrode for alk. batteries having good bond between the Cd paste and the substrate. In an example, a dispersion contg. CM-cellulose 2, carbonyl Ni powder 50 g, and H2O 300 cm3 was sprayed on a porous Ni foil and the coated foil was sintered at 900-1200 degrees for 5-60 min. A paste contg. CdO 100, Ni powder 10, poly(vinyl alc.) 4 g, and H2O 40 cm3 was coated (0.7 mm) on the sintered Ni layer, the electrode was electrochem. treated and pressed to reduce the total thickness to 0.6 mm.
A 3-plylaminated electrode comprises a central conductive sheet of Pb foil, thin perforated Pb sheet or paper sheet contg. graphite or Pb metal powder, sandwiched between outer plies of porous compressed and sintered dry mats consisting of a homogeneous mixt. of synthetic fibres and active material the fibres being 90-100% synthetic, remainder natural fibres, and the active material being from PbO, Pb and tetra-and tri-basic PbSO4 coated on the fibres with 50-99 pts. active material per pt fibres, forming a strong, close bonded laminate. The electrode is made by (a) dispersing fibres in water to form a slurry, (b) adding active material powder and thoroughly mixing, (c) flocculating by lowering the pH until a large flocculated mass of fibres and active material is formed (d) filtering and drying to form a composite sheet of a loose homogeneous mass of active material coated fibres, (e) placing a sheet of the homogeneous mass on each side of a conductive sheet to form a sandwich and (f) heating at 120-200 degrees C. and compressing at atmospheric press. -13,000 psi to form the electrode. The plates are 30-50% lighter than pasted grids contg. the same amt. of active material and can be bent into irregular shapes.
Alkaline battery comprises a separator and an electrolyte-holding member positioned between an anode and a cathode, comprising an alkali-resistant porous member (nylon nonwoven fabric or cloth) impregnated with a surface active agent (non-ion surface active agent). It is possible to increase electrolyte-absorbing rate and to distribute the electrolyte uniformly in the electrolyte-holding member by increasing electrolyte-absorbing ability without reducing electrolyte-holding ability of the electrolyte-holding member. Battery has electrolyte-absorbing rate ten to thirty times the conventional alkaline battery, electrolyte-holding amt. 5 to 10% more than the conventional alkaline battery, long charge-discharge cycle life and excellent efficiency.
An alkaline battery, having zinc as anode active material, has a separator for preventing permeation of zincate ions. The separator is made by wetting an alkali-resistant porous member with a surfactant, the impregnating the member with a mixt. of a borom oxide cpd., an alkali-resistant gelling agent and polyvinyl alcohol. As alkali-resistant member, cloth or nonwoven fabric, such as vinyl formal, polyamide or polypropylene is used. As boron oxide cpd., boric acid, boron oxide or metaboric acid is used. As an alkali-resistant gelling agent, polyacrylic soda is used. The separator has no pinholes; the battery has improved charge-discharge life.
A secondary battery contains as appropriate cathode, a Zn anode, an aq. alk. electrolyte contg. polycationic polymers, and a Ti auxiliary anode placed between the cathode and the anode. The use of the auxiliary anode and addn. of the polycationic polymer prevent the formation of Zn dendrites and generation of H at the anode. In an example, NiO cathodes, Zn anodes prepd. by coating a Ni screen with ZnO paste and subsequently reducing the ZnO electrolytically Ti screen auxiliary anodes, and cellulose separators were arranged in a battery container with a 7N KOH electrolyte contg. 1% polycationic polymer prepd. by reacting 1,5-dichloropentane with N,N,N','-tetramethyltrimethylenediamine in DMF. The battery had a better service life then the conventional batteries.
A mixt. of powd. MnO2 and C is made into a flexible sheet-line cathode for multilayer battery by using poly(tetrafluoroethylene)) as the binder. The use of poly(tetrafluoroethylene) improves the flexibility of the electrode film and films do not crack during drying. In an example, electrolytic MnO2 powder (-325 mesh) 70 and acetylene black 30 g were mixed well, the mixt. was kneaded with 30 cm3 H2O and a dispersion of poly(tetrafluoroethylene) (5 parts polymer/100 parts MnO2-C mixt.) was added to the mixt. The mixt. was press rolled and dried at room temp. to give 1mm thick flexible cathode film for multilayer battery.
Battery cases for accumulators made from polyolefins with coal dust as filler, esp. from polypropylene and its copolymers, and stabilised with anti-oxidants, pref. phenol derivs., amines and/or thio cpds. Cost of the polyolefin is reduced and resistance to oxidn. during processing or use is improved. Production is cheap and simple, and the products have good mechanical properties (tensile strength and impact resistance). 40-50 wt.% coal dust is mixed with the polypropylene or its copolymers e.g. with ethylene. The dust consists of anthracite or coal, with ash content 10-18 wt.% and particle size below 100, pref. below 70 mu m. Amount of anti-oxidant is 0.01-0.3 wt.% pref. consisting of a steric-hindered polymeric phenol which gives around 20 times higher heat-stability than from unstabilised compsns.
Process for producing a melt-blown non-woven mat battery separator wherein a fibre-forming thermoplastic polymer resin is extruded in molten form from orifices of a heated nozzle into a stream of hot inert gas which attenuates the molten resin into fibres that form a fibre stream and the fibres are collected on a receiver in the path of the fibre stream to form the non-woven mat. Process comprises (a) producing the mat of high resin flow rates, which comprises extruding from the nozzle orifices, at a resin flow wate of &gt;0.1g/min. per orifice, a fibre-forming thermoplastic polymer resin degraded to have both an intrinsic viscosity of 0.6-&lt;1.4 and an apparent viscosity in the nozzle orifices of 50-300P. (b) collecting the fibres on the receiver in a basis wt. of 100-400g/in2. (c) compacting the fibres to a mat thickness of 10-50 mils and a porosity (percent void fraction) &gt;40% 5-20 degrees F above the softening pt. of the thermoplastic and 5-35 degrees F below the m.pt. of thermoplastics utilising fixed spacers or shims at (i) a pressure of about 1-10 psi and (ii) a time interval of from 0.01-30 secs. wherein the spacers or shims prevent large pressures from being applied directly to the mat surfaces, and (d) producing a battery separator having an electrical resistance &lt;0.040 ohms/in2.
A plastics container, such as a battery case, of the type having partitions internally subdividing it into separate chambers is made by injection between a mould element and a former comprising spaced cores, the spaces between which define the partitions. Each core carries, at its free end an element which engages an oppositely located injection gate in the bottom wall of the mould element during the initial stages of injection and which is withdrawn during the final stages to allow completion of the bottom wall of the container. Positive restraint of the cores during injection gives a uniformly walled article.
An electrochemical cell electrode is produced from a substrate of fibrous carbon paper by coating with pyrolytic carbon to form electrically conductive bonds between the fibres, impregnating with a hydrophobic polymer, and sintering at 580-630 degrees F after which a surface coating of hydrophobic polymer and catalyst is applied. Preferably the impregnation step utilises 5-40% by wt. of polytetrafluoroethylene. The paper retans a low electrical resistivity e.g. 0.02-0.05 ohm-cm. after impregnation and remains water resistant over long periods of separation. A metal backing screen is unnecessary while very low surface catalyst loadings are possible.
The alkaline storage battery has an anode electrode comprising a zinc sheet and a coating layer of mixt. of polyvinyl alcohol and (hydr)oxide of Mg, Ti, Zr, Al or Th. The contact surface of the anode electrode to electrolyte is increased and the anode electrode preserves the electrolyte firmly to improve life time of the battery.
The cells have positive electrodes in contact with a fibrous sheet of a kneaded body of powdered active material and soln. suspended fluorine resin. Rapid charging of the cells is possible.
Method comprises forming a non-woven cloth by piling up nylon fibres having an av. fineness &lt;0.1 denier in an irregular manner to form fibre entangled portions, wetting the non-woven cloth with alcohol soln. contg. inorganic salt which reacts with alkali to form alkali-resistant hydroxide, adhesively binding the fibrous entangled portions of the non-woven cloth with the alcohol soln. at the same time as depositing the inorganic salt on the surface of the fibre, and then wetting the non-woven cloth with alkaline soln. to replace the inorganic salt with hydroxide.
Process for mfg. moulded green ceramic compacts which, after calcining, contain beta"-alumina of high density the novelty being the use of (a) 2.5-4.5 pts. wt. of a ceramic contg. by wt. 80% min. alumina and 5-15% Na2O; with (b) 1 pt. wt. of a binder contg. 20-35% polyvinyl pyrrolidine (PVP) with average mol. wt. (AMW) 20,000-160,000, and 80-65% ethylene glycol; the mixt. is extruded through a nozzle to form the desired shape, which is heated to evaporate the glycol and burn out the PVP. The PVP pref. has AMW 30,000-50,000, esp. 40,000, whereas the extrusion pressure is pref. 3000-50,000 psi using a speed of 0.63-125 cm/min. The modified beta-alumina is used in separators and solid electrolytes for prim. or sec. batteries and thermoelectric generators.
A mouldable resin mixture comprises (a) 25-95 wt.% graphite powder; (b) 5-75 wt.% branched polyphenylene comprising benzene ring structures bonded into a polymer chain, the polymer being characterised by a linear infrared absorbence spectrum integrated peak area within the 726-930 cm-1 frequency range having the following distribution: 10-18% within the range 854-936 cm-1, 15-30% in the range 850-853 cm-1, 13-20% in the range 778-805 cm-1 and the remainder within the range 726-777 cm-1; and (c) 0-30% branched nitropolyphenylene comprising benzene ring structures bonded into a polymer chain and contg. 0.25-15 wt. % nitrogen, this polymer being characterised by infrare absorbances at 1345 cm-1 and 1525 cm-1 and having 8% of the linear infrared absorbence spectrum integrated peak area between 726 and 930 cm-1 within the range 856-930 cm-1.
Separator for an alkaline storage battery having improved discharge properties and long life is obtd. by (1) providing a base of nonwoven fabric and (2) adhering cpd. contg. polyoxyethylene radical -(CH2CH2O)n- onto the base to form the separator. The separator is easily wetted by alkali electrolyte, so that an alkaline battery contg. the separator has high discharge properties.
Electrode is prepd. by pressing iron powder with elastic material such as synthetic rubber to form a body and sintering the body or sintering the iron powder and pressing the sintered body. The discharge of the alkali storage battery is improved.
Galvanic cell uses a negative electrode made of light metal, a non-aq. electrolyte, and a positive electrode made of a fluorinated carbon cpd. polymer contg. chlorine atoms in addn. to the fluorine atoms. The reducible material of the positive electrode pref. uses (a) polytrifluoro-chloroethylene; (b) a polymer of 1,1-difluoro-2-chloroethylene; or (c) a copolymer of trifluorochloroethylene and vinylidene chloride. The polymer pref. has mol. wt. 70000-500000, esp. 200000-300000 and is mixed in the ratio of 85:15 with graphite; and the pref. negative electrode is lithium. The batteries have a high voltage and high energy density, plus a high permissible discharge current density; their long storage life makes them very suitable for driving expensive electronic equipment which is only used intermittently.
A dendrite barrier is formed across the entire face of a Zn negative electrode in a Zn-alkali electrolyte battery which is subject of dendrite formation and shorting on charge, the barrier comprising (a) a barrier layer formed by a cloth substrate of porous flexible material having a porous metal of low H overvoltage deposited on and through it, which, on contact with a dendrite reacts with it to dissolve Zn and prevent shorting, (b) a porous absorbent layer between the Zn electrode and barrier layer and (c) a confining separator layer across the outer face of the barrier layer, capable of deffusing electrolyte but not dissolved Zn.
Rechargeable Ni-Zn battery with foil negative electrode (I) of or contg. Zn cpds. and a foil positive electrode (II) of Ni oxide, with a separator, electrolyte absorber, and alkali electrolyte. The novelty is that electrode (I) has a current collector carrying a mixt. of fluoroplastic and, by wt. 3-20% K2O and/or KOH, 1-20% Bi2O3, CdO and/or Cd(OH)2, the remainder being Zn, ZnO and/or Zn(OH)2, the theoretical capacity/power of electrode (II) is 1/4 to 1/2 that of electrode (i), the separator is a non-woven foil coated with polyvinyl alcohol (PVA) and a boron cpd., the absorber is an alkali-resistant porous foil impregnated with PVA and an oxide, and the amt. of electrolyte is 1.0-1.7 ml per ampere-hour of the theoretical capacity/power of electrode (I). This battery has a long cyclic life and can replace dry batteries.
A lithium-iodine cell comprises an iodine contg. cathode region having at least two surface portions and a current collector spaced from the surface portions, a cathode conductor connected to the collector, first and second lithium anodes each having a planar portion with opposite surfaces, one surface of each anode contacting the cathode material, first and second cup-shaped anode holders embracing the anodes, the rim of one holder being receceived within the rim of the other, with the cathode conductor extending between therims and insulated from the anodes by insulating separators disposed between the rims and embracing part of the cathode conductor, and anode conductors connected to the anodes. The device is esp. a cell for an implantable cardiac pacemaker, provides a relatively larger lithium anode area with small overall size and constrains iodine migration.
Electrode having advantage of long life has active material with admixture of surface dispersing agent containing block copolymer of polyethylene oxide with highly molecular hydrophobic component e.g. 0.1-1% of polyoxypropylene. This also stabilises electrical characteristics of the electrode.
A lead storage cell separator comprises thermally fused and bound thermally fusible resin fibre, and water-sol. binder painted it. The total thickness is &lt;0.3 mm.
Cell separator is mfd. by extruding fused mixture of foaming materials, thermoplastic resin, and interface activator from a slit die; pulling the extruded fused mixture with rapid cooling to form a sheet-like structure having cracks; laminating two sheets with the same crack direction; enlarging the sheet structures in the direction perpendicular to the crack direction to obtain fibrous collections; impregnating with aq. resin; and thermally treating.
Electric battery comprising a transport device having one or a number of handles articulated to an intermediate piece fixed to the battery or forming a part thereof, so that the handles, intermediate part and articulation form one and the same element.    Advantageously, the intermediate part has recesses for the opening of the respective elements of the battery. Provides a device permitting transport of the body combined with other functions e.g. protection of the terminals and closing of the air vent apertures. The battery and the transport attachment are pref. constructed of polypropylene.
Preformed cathode for an electrochemical cell, consists of a semi-rigid component with a prescribed shape, and compsn. by wt. 40-99% soot, 1% min. of a mechanical binder which is inert in the cell, and the remainder graphite. The binder is pref. a fluorocarbon polymer, esp. PTFE or Kel-F(RTM), used in the amt. of 1-10%, with 65-9% soot and 0-30% graphite. The soot is pref. made into a suspension in a suitable liq. followed by adding the binder and moulding a suitable shape which is hardened. The cell pref. employs an alkali metal anode and a soluble depolariser, eso. a Li anode where the depolariser is POCl3, SOCl2 or SO2Cl2. The cathode contains a large amt. of active carbon, can easily be made by automated mass prodn. methods, and the incidence of internal short circuits is greatly reduced.
A curable compsn. for producing a battery container or cover having improved combined properties of surface hardness, impact strength, and flexural modulus comprises, a mixt. of 9 wt.% of a rubber hydrocarbon polymer selected from natural rubber, copolymers of butadiene styrene or butadiene acrylonitrile, and compatible mixts. of the natural rubber and/or the copolymers, 75 wt.% of the compsn. of a filler consisting of finely divided petroleum coke, 13 wt. % of the rubber hydrocarbon content of sulphur, 0.27 wt.% of the compsn. of an accelerator, and the remainder of the compsn. being made up of suitable quantities of activator and plasticiser. The moulded articles from the compsn. have critical physical properties and are resistant to harsh chemicals such as battery electrolyte. The compsn. utilises cheap petroleum coke as filler instead of anthracite coal dust.
A galvanic cell comprises a container contg. a depolariser mix and having an open end, a carbon collector rod projecting centrally from the mix and a plastics closure covering the open end of the container. The closure is provided with an inner tubular neck through which the rod passes and to which it is bonded by adhesive and a peripheral skirt which embraces the rim of the container and which is also bonded to it by adhesive. The tubular sleeve may be upwardly or downwardly directed and the closure may be provided with an opening, either subsequently sealed after application of the closure or left open to form part of the cell venting system. The pref. thickness of the closure is 0.005-0.06". Process does not involve the use of asphalt.
A hollow, multi-layered cross-linked, plastic structure is produced from a linear thermoplastic polyester and a cross-linkable polyethylene having a m. pt. lower than the m. pt of the polyester, comprises, charging a mould with a sufficient amt. of the polyester material to form a substantially uniform layer on the inner surface of the mould, heating the mould to a temp. above the mpt of the polyester, rotating the mould to fuse the polyester and to uniformly distribute on the inner surface of the mould, cooling the mould to a temp. below the m. pt. of the polyester but above the,. pt. of the cross-linkable polyethylene to crystallise the polyester to a solid layer, stopping the rotation of the mould, charging the mould with a sufficient amt. of the cross-linkable polyethylene to form a uniform layer on the polyester layer, heating the mould to a temp. above the m. pt. of the polyethylene and below the m. pt. of the polyester so as not to cause dimensional mould for a sufficient period of time to fuse uniformly distribute and crosslink the polyethylene on the inner surface of the polyester layer, and stopping the rotation to remove the resulting hollow, cross-linked multi-layered polymeric structure.
Battery for encapsulating in a heart stimulator (pacemaker) by means of a synthetic resin has a positive electrode contg. mercuric oxide as depolariser, a negative electrode of amalgamated zinc powder, an alkaline electrolyte, a nickel-plated steel housing surrounding the positive electrode, a cover of a resilient laminate surrounding the negative electrode, and a sealing ring placed between the edge region of the cover and the housing, this ring consisting of an electrically insulating synthetic resin with a good resistance towards the electrolyte. In order to retain the resilient action of the cover, after the battery has been encapsulated in the synthetic resin, annular devices surrounds at least a part of the outer surface of the cover for holding-away the synthetic resin from the transition region of the housing towards the cover.
A laminated dry cell includes laminated unit cell each covered with wax consisting of polypropylene of mol. wt. 5000-20000 or polypropylene contg. ethylene glycol.
The anode is mfd. from a mixt. of 6-15 wt % of carboxymethyl cellulose or Na polyacrylate (based on the aq. KOH) soln.), 30-40 wt % aq. KOH soln. and a metal activator.
Method for making a gas diffusing electrode having a water proofing layer on the gas side of a porous electrode, in that a fluoro-resin layer is heat treated in a alkaline soln. and treated with a soln. which does not contain soluble materials, such as Cu, Mg and Al, to make a water proof fluoro resin layer. The fluoro-resin layer is obtained for example, a porous, un-woven cloth of fluoro-resin which is made by polymerization using Cu, Mg or Al as the catalyst. The gas diffusing electrode has improved liquid leakage resistance and long life.
Method for making a gas diffusion electrode comprises compressing fluorine resins on the gas side of a Ni system porous electrode body at a first pressure such as 100-150 Kg/cm2) to form a first porous fluorine resin layer (having pores of 5-25 mu diameter), and compressing fluorine resins on the first fluorine resin layer at a second pressure (such as 50-120 Kg/cm2) to form a second porous fluorine resin layer (having pores of 0.5-2 mu diameter). A sufficiently large amt. of gas is supplied during charging process, and a battery which employs this gas diffusion electrode has improved liq. leakage resistance.
A rechargeable battery comprises a positive electrode, a negative electrode, and a separator which comprises a first layer of porous material having good electrolyte resistance and good oxidation resistance, and a second layer of a grafted cpd. of polyethylene and acrylic acid, the first layer being in contact with the positive electrode, and the second layer being in contact with the negative electrode. The battery has improved charging properties.
A rechargeable battery comprises a positive electrode, a rechargeable negative electrode, an auxiliary electrode for charge, and a porous separator of good electrolyte resistance and oxidation resistance, the porous separator being coated with a film which comprises a grafted cpd. of polyethylene and acrylic acid. The battery has improved charge and discharge properties.
Nickel-zinc-alkali-accumulator with a +ve Ni electrode, and a -ve Zn electrode of higher capacity than the +ve electrode, the -ve electrode being directly surrounded by a sepg. element of non-woven cellulose, followed by a semipermeable cellulose membrane and a a microporous plastic foil in contact with the +ve electrode; the amt. of aq. KOH electrolyte is controlled so that free electrolyte is only present on the two electrodes and in the sepg. element; and the accumulator contains a gas-phase reaction catalyst for theoxygen and hydrogen formed at the end of the charging cycle. The electrolyte is pref. 5-7 Mol/1 KOH in water, the amt. used being 1.7-2.1 ml per Ah of the negative active material. The catalyst is Pt in artificial graphite. An inexpensive accumulator with long life, where the amt. of electrolyte and the sepg. element reduce the formation of zinc dendrites.
Fuel cell stack cooling system comprises an electrically conductive separator plate between adjacent cells in the stack, each separator plate having, in addition to two channels for carrying reactant gases into communication with the cell electrodes, passageways in at least one of its surfaces in which are disposed cooler tubes to the channels. Preferably the passageways alternate with and are parallel to the channels. The coolant specifically comprises water and the cooler tubes copper tubes (60) coated with a dielectric material comprising fluorocarbon polymer.
The dry cell comprises a heat contraction tubes, a cathode mixts. inserted into the tube, and a zinc can for accommodating the heat-contracted tube, the heat contraction tube being produced by adding a plasticiser to PVA, injection-moulding the mixt. and inflating the injection mouldings.
A separator for an alkaline dry cell comprises paper or nonwoven fabric consisting of 30-70% cellulose fibres and 5-30% of easily soluble polyvinyl alcohol fibres and bonded portions of the paper or nonwoven fabric broken partially by pressing or crumpling treatments, whereby a speed of liquid absorption is &lt;3 mins. The separator has excellent alkali-resistance, good liquid absorption due to partial breakage of the bonded portions, and is compact.
Electrochemical battery, the novelty being that it consists of a lithium anode and a conducting cathode, connected via an organic electrolyte contg. carbon disulphide at least partially in soln. The battery pref. also contains free sulphur in the vicinity of the cathode or mixed with the latter, the cathode consisting at least partly of carbon. The ratio, free S:CS2, esp. when the sulphur is mixed with the carbon in the cathode, is pref. 0.5-1.5, esp. 1. The electrolyte is pref. an organic solvent contg. e.g. lithium perchlorate, esp. dimethylsulphoxide; propylene carbonate; the dimethyl ether of ethylene glycol; or other solvents listed in the claims. The electrolyte is pref. satd. with lithium trithiocarbonate. Conventional Li-S batteries are subject to self-discharge, which has restricted their use in the past. The invention eliminates this problem and also eliminates the need to use SO2 in cells of this type.
Membrane for electrochemical cells comprises (a) an inert polymeric base film and (b) a polymerised perfluorovinyl cpd., e.g. sulphonated alpha, beta-beta-trifluoro-styrene which is grafted onto the film by irradiation. The membrane may be formed dissolving the perfluorovinyl cpd. in an inert organic solvent, bringing the soln. in contact with an inert polymer film, irradiating the film to graft polymerise the perfluorovinyl cpd. on the film to graft polymerise the sulphonating the grafted film. Claims also a method of effecting polymerisation of alpha, beta-beta-trifluorostyrene by irradiation. The membrane may be used as ion-exchange membrane in chloralkali electrolysis cells and fuel cells. The inert base film can be of polypropylene, polyethylene, polytetrafluoroethylene, polytrifluorochloroethylene, tetrafluoro-ethylene/hexafluoropropylene-copolymer, tetrafluoroethylene/ethylene copolymer and/or a laminate of such films. The fluorinated vinyl monomers include those of general formula where x = an integer from 0 to 8 which can be graft polymerised on the film alone or together with comonomers, e.g. alpha-methyl-styrene. The irradiation may be effected with a Co-60-gamma-ray source, e.g. with a total dose of 0.1 to 10.0 M rad and attempts. between -78 degrees and 60 degrees C. Sulphonataion may be carried out in a chlorosulphonic acid bath, e.g. at conc.
The cell includes a hydrophilic separator which surrounds the anode, pref. made of Zn and consisting of a cylindrical mesh filled with active metal particles. The cathode consists of a cylindrical hydrophobic polymer, pref P.T.F.E contacting on its inner surface a catalytic metal consisting of a Gp IB or VIII metal or alloy. The cathode is bonded to a spacer or casing element forming a liquid tight seal, this spacer typically being made of polyethylene. The cell is activated by puncturing a thin flexible water reservoir made of hydrophobic plastic membrane using a needle attached to a threaded member protruding through the spacer. An outer shield over the cell is spaced from the cathode by the spacer, the outer periphery of which is notched to allow air into the cathode.
Soluble high molecular substances are dissolved 3-70 w/w% in a solvent, thereby components which can be removed by freeze-drying e.g. non-solvent of the high molecular substance, may be added. Then the soln. is spread on a plate or in a cylinder, and the solvent is removed under reduced pressure at temp. below freezing point of the solvent. As the soluble high molecular substance any high molecular substance which is soluble above 3 w/w% in a suitable inorganic or organic solvent, can be used. By this method, the variation in diameter of micropores is very small, size of micropores can be regulated freely. The method can be applied to almost all high molecular substances.
A separator is made of a double layer of a thin ion-permeable synthetic resin film or a thin cellophane film and and alkaline-resisting synthetic fibrous nonwoven cloth. The peripheral portion of the nonwoven portion is given an ion-permeable, minute structure by thermal fusing.
A button type AgO or HgO alkaline cell has three layers and comprises an electrolyte absorbing body, an ion-penetrating film and a blocking member; the three layers being constructed to form a separator, a cathode electrode in contact with the electrolyte absorbing body and an anode electrode being in contact with the blocking member. The absorbing body is made of woven viscose rayon fibre and insoluble PVA fibre combined irregularly by soluble PVA fibre. The blocking member is made by perforated high crystalline plastic film having a plurality of long holes.
Accumulator electrode plates are treated for the removal of water with a heated liq. with higher b. pt. than water, the plates being enclosed in a non-porous foil beforehand which is resistant to the liq. Pref. the foil is polyethylene or PVC, and which is reinforced. The liq. medium used may be petroleum, glycol, halogenated hydrocarbons etc. Produces long storage electrodes and is partic. for lead battery negative electrodes which are liable to oxidise and also cadmium electrodes of alkaline accumulators.
Water-curable urethane polymers are used as gelling agents for dry battery electrolytes. In an example, an electrolyte 85 was mixed with CM-cellulose 5 and 10 pts. of a water-curable urethane polymer, which was prepd. from a mixt. contg. poly(oxyethylene-oxypropylene)glycerol ether (mol. wt. 7800) 89 and tolylene diisocyanate (TDI-80) 11% by addn. polymn., to prepare an electrolyte paste. When a dry battery made with the electrolyte paste was discharged at 20 degrees C for 48 hr, to softening or overflowing of the electrolyte paste was observed.
A thin web of nonwoven C fibres for use a fuel cell electrode substrate is prepd. by (a) spinning carbonaceous pitch fibre having a mesophase content of 40-90 wt.% from a similar, nonthixotropic pitch, under quiescent conditions forms a homogeneous bulk mesophase having large coalesced domains (b) disposing staple lengths of spun fibre intimately contacting each other in a nonwoven fibrous web, (c) heating in a oxidising atmos. to thermoset the fibres so that they maintain their shape at more elevated temps., (de further heating to a carbonising temp. in an O-free atmos. to expel hydrogen and other volatiles, and (e) impregnating the web with 0.05-0.5 kg fused hydrophobic resin/m2 web to increase it structural integrity and hydrophobicity. The electrodes have high porosity, high conductance and are thermally stable and chemically inert. They do not require bonding with carbonised resin or coating with pyrolytic C for use, avoiding many prodn. difficulties. They may be used as anode or cathode substrates with acid, alkaline or other types of electrolytes.
An anode for an electrochemical cell comprises a porous anodic metal body wrapped in two layers of different and distinct materials, the firt being gas impermeable in contact with an aq. electrolyte, hydrophilic and ion permeable and the second being gas permeable when in contact with an aq. electrolyte, hydrophilic dimensionally stable and heat sealable. The anode is esp. useful in a metal/air cell. It can be rapidly charged and discharged without migration of reactant species.
A porous electrode plate contg. a catalyst is treated with fluoro resin. A first porous layer composed of fluoro resin and carbon or metal oxide is formed on one surface of the plate. Then a second porous layer composed of fluoro resin dissolved in an organic solvent and carbon or metal oxide is formed on the first porous layer.
After a catalyst is added to a porous electrode plate, it is treated with fluorine resin. First and second porous layers composed of fluorine resin and carbon or metal oxide are successively formed on one surface of the electrode plate, and the electrode plate is heat-treated to obtain an air electrode.
Molten synthetic resin is applied to the surface fo a flexible synthetic-resin separator sheet with an applicator in corrugated form and solidified. The separator sheet is shaped in a bag form, and electrodes are arranged in it to obtain Pb batteries. The process improves workability and reduces the prodn. cost. In an example, 0.15 mm thick separator film (elc. resistance in H2SO4 at 25 degrees 0.0006 /dm2) made form poly(vinyl chloride) and nonwoven polyester fabric ws coated with a molten olefin resin at 170 degrees in a corrugated form.
A Zn anode is produced from a mixt. contg. powdered Zn, ZnO, or Zn(OH)2; powdered oxides or hydroxides of a metal more noble than Zn; and alkali resistant carboxy-type polymers and high mol. wt. cpds. as binders. The anode has improved discharge capacity at low temps. and heavy loads and improved charge-discharge cycle characteristics. In an example, powdered mixt. of Zn 35, ZnO 35, BiO 10, In2O3 5, poly(acrylic acid) Na salt 5, and "teflon" (RTM) 10% were mixed and kneaded with a suitable amt. of H2O.
An electric battery comprises a metal based negative electrode and a porous positive electrode at least the ion exchanging surface of which is covered with a semi-permeable membrane, pref. made of polyvinyl alcohol, insolubilised by cross-linking. The layer is obtd. by applying a soln. contg. polyvinyl alcohol, a cross-linking agent and an acid cpd. then drying and heating the layer. The provision of the semi-permeable membrane overcomes and prevents possible short circuiting due to electrode contact.
A separator for an electrochemical generator comprises at least one porous layer one face of which is covered with at least one semi-permeable membrane made of polyvinyl alcohol which has been made water-insoluble by cross-linking. The layer is obtd. by applying a soln. contg. polyvinyl alcohol, a cross-linking agent, and an acid cpd. then drying and heating the layer. The separators are esp. used in accumulations they are stable not fragile and do not swell.
Negative electrodes for a lead battery having long life, contains as active materials, polyethylene oxide, or polyethylene oxide and lignins.
An attachment for a multi-cell battery on to two flat surfaces at right angles to each other, the battery resting on one of them, has a fixing parallel to the common edges of those surfaces but on the diagonally opposite side and is screwed down towards that edge, this fixing presses down vertically against 1 part of the cells but not on to the edge of the battery box. Eliminates problems of wedges and gives firm mounting. The fixing is pref. aninsulant e.g. nylon or polypropylene.
A separator preventing short circuit between negative and positive electrodes in an alkaline secondary battery is fabricated by immersing a base film of low density polyethylene in an organic solvent soln. of acrylic or methacrylic acid (deriv.) and irradiating the immersed base film to graft-copolymerise the polyethylene and acrylic acid or methacrylic (deriv.) to the graft rate of 45-100%. The separator has few pinholes and low electric resistance.
The Li-I2 cell, with a cathode contg. a charge transfer complex (I) of an organic donor component (II) and I2, has a Li anode with a surface to which the cathode is connected, with a coating of an organic electron donor. (III). (III) can be the same as (II) or a polyvinylpyridine polymer, esp. a 2-vinylpyridine polymer. A series of coatings can be used. These cells can be used for supplying current to inaccessible equipment, e.g. implanted heart pacers, as well as for other purposes. The cells, esp. the anodes, are of improved construction and can be produced easily and economically. The cell impedance is relatively low and stable for long periods.
Lead-acid storage battery comprises a case and a cover both or either of which is made of polypropylene, and two polypropylene lifting lugs mounted on opposite sides of the battery. A portion of each lug extends above the top of the battery, and includes a hole for releasably receiving the end of a carrying strap. The lugs are diagonally opposed to each other, so that on insertion of the strap, the centre of gravity lies beneath the centre of the strap. The lugs are flexed during mfr. to provide a tough pliant hinge section just above the top of the battery, so that the lug portions above the top of the battery can be folded down repeatedly on onto the battery.
A polymeric article of porosity 40% provided by ultrafine, uniformly-distributed, continuous interconnecting pores of ida. 40-120 angstroms is prepd. by heating a solid thermoplastic polymer of crystallinity 70% (or its blends with is not &gt;50 wt. % of a similar polymer of is not &gt;65% crystallinity) to at least melting temp. range; forming a composite body by incorporating a salt of formula (I) (Z = alkali metal opt. mixed with alkaline earths, R1 = H, 1-4C alkyl, aryl or halo, R2 = H, 1-4C alkyl, aryl or halo) at 70-85 wt. % of total composite; sahping at this temp % cooling to give a solid and dissolving out (I). Used as a separator for head-acid batteries but also for filters, stamp pads; surface coatings; thermal insulation and (after incorporation of a conductive solid) as electrodes for fuel cells or in decorative articles etc. Use of (II) gives much finer pores than conventional matls. Such as Na2CO3 or NaCl.
A gas diffusion type electrode for electrochemical fuel cell or metal-air battery, consists of first layers of porous hydrophobic material which alternate with second layers of porous hydrophilic material contg. catalyst. The layers are clearly defined and extend from one face which will be exposed to electrolyte, to an opposite face which will be exposed to gaseous fuel reactant. Such electrodes are formed by building up a composite by deposition if the second layers on alternate layers of the first material, and slicing electrode sheets from the composite in planes perpendicular to the original layers. The terms 'hydrophobic' and 'hydrophilic' are with respect to the electrolyte. The electrode gives maximum catalyst utilisation and minimum resistance to flow of reactants, products, ions and electrons.
Method of making an anode plate for an alkaline storage battery wherein formation of the plate is simplified and active material is not peeled off. The anode plate is made by packing cadmium paste into a porous substrate. The anode plate is charged to 60 to 80% of its capacity during formation. In an example, a first mixt. is prepd. by blending 2 g. of PVA, 5 g. of CMC and 100 ml of ethylene glycol. A second mixt. is produced by mixing cadmium oxide powder and nickel powder in the ratio 8:2. Paste-like active material is prepared by mixing the first and second mixts.    The active mixt. is packed into and coated on both sides of a porous nickel plate with a porosity of 60%, dried at 120 degrees C for 4 to 5 hr, and pressed at a pressure of 100 kg/cm2. The electrode plate is charged in a KOH soln.
Accumulator, with two electrodes of the first type applied to base-electrodes, where the active mass on the positive side contains MnO2, and an acid electrolyte is used. The negative side of the base electrode consists of graphite powder embedded in a binder which withstands the electrolyte, whereas the positive side consists of a coarse porous structure of graphite or of ti coated with Ti-nitride or -carbide, with average pore dia. 0.1-2 mm and pore vol. 20-70%. The binder is pref. polythene, polypropylene, or PVC, and the graphite powder pref. has a grain size of 1-500 mu. The active mass on the negative side is pref. Pb, Fe, Cd, Mn, or esp. Zn. See also 2451472. For example, the accumulator may be used in driving electric vehicles, the object being to obtain max. watt-hours per kg of accumulator wt. High performance is achieved even after repeated charging and discharging.
A thin plat anode assembly comprises (a) an electrically conductive organic resin substrate and (b) a coating of Zn dust adhered by dried polymer particles formed from solvent swollen aq. latex particles of compatible organic polymeric binder, with 0.5-5 wt.% polymer binder based on Zn dust. The swollen latex forms a stable suspension of Zn for coating. The amt. used forms a discontinuous coating, which holds the Zn particles together. The polymer binder is pref. a copolymer of ethyle acrylate and 2-sulphoethyl acrylate.
A multicell alkaline cell battery comprises first and second cells each having a top and a metallic container attached to the top, within which ara an anode mixt, a cathode mix in contact with the container, a separator, and an electrolyte, one cell having a metallic current collector attached to the bottom of and extending away from the container and this current collector passing through the top of the second cell and being embedded in the anode mix. The cell to cell contact is short in length and electrically solid. The battery has fewer parts and can be produced at lower cost. Has inherent stiffness, requiring a lighter outside covering. Individual cells may be stored without deterioration before battery assembly.
An electrode of a rechargeable cell of positive and negative electrodes, a separator and an electrolyte, consists of a foraminous electrically conductive substrate supporting a paste of (a) finely divided, particulate, rechargeable active material and (b) a fibrous inter-connecting network of unsintered, uncoalesced, hydrophobic linear fluorocarbon polymer with active material dispersed throughout and bound in the network, so being high accessible to electrolyte and gas generated during overcharge. Alternatively, the unsintered polymer and the active material are dispersed in the pores of a sintered porous plaque of bonded metal powder. The cell exhibits enhanced gas recombination, e.g. for negative Cd electrodes an internal pressurisation of 22.5 psia compared with 73.0 psia for conventional, and increased capacity and cycle life, e.g. 70-75% capacity retention after 50 cycles for a Zn electrode shorting after 13 cycles when sintered PTFE is used.
Electrical contact with the can electrode of an electric cell, is made through an outer conductive bottom member which embraces the lower periphery of the can and makes contact with the bottom wall of the can. An outer tubular plastic shell is swaged inwardly at the end over a peripheral lip of the bottom member so as to grip the lip and seal off this end of the can. A central carbon rod electrode projects from the other end of the cell. The shell end is swaged over by heat softening and the use of swaging dies. The swaged end is pref. secured and sealed with a hot melt or epoxy resin adhesive.
The lead-acid accumulation battery is intended for use in motor vehicles. The probe includes a container filled with water or an aq. soln. At least one of its walls is immersed in the electrolyte; and is permeable to water, but not to substances dissolved in the electrolyte. The probe has a sensor which responds to the probe variables depending on the battery state of charge. Specif., the probe aq. soln. is dil. H2SO4. The wall of the probe, immersed in the electrolyte may be of a porous ceramics or glass, rendered hydrophobic, or it may be of porous PTFE.
A sealing matl. for dry cells comprises: 15-25 wt.% amorphous polypropylene of ave. mol. wt. 6000-9000; 15-5 wt% of polyirobutylene of ave. mol. wt. 750-1500; and 70 wt% turpentine (deriv). of softening pt. 75-100 degrees C.
Cathode mixture for a dry cell contains an acrylate binder. The dry cell has good stability against manganese dioxide and good storage performance.
A sealed type alkaline storage battery comprises a metal container having at its inner surface an exposed layer of nickel and polytetrafluoroethylene resin, and a generating unit packed into the metal container. Explosion of the battery is prevented and its charging is performed for a short period.
A cathode for a sea water battery having improved mechanical strength, high speed activity and a good rising voltage, comprises a formed body of cathode active material or a porous metal substrate filled with the cathode active material, consisting of halide or oxide of copper, lead or mercury. The formed body or metal substrate is coated with a water-soluble thin film or a thin film capable of being easily peeled off when it comes in contact with water. The thin film is formed by immersing the formed body or emtal substrate in an aq. soln. of carboxy methylcellulose or a suspension of high molecular material.
A battery having high voltage and high energy density, uses alkali metal such as Li, Ma or K as an anode, thionyl chloride as an electrolyte and cathode active material, and a carbon body comprising carbon powder and carbon fibres as a cathode. An anode is made by adhesively bonding a Li thiin plate to a Ni net.    A cathode is made by embedding a Ni net in a pastelike mixt. contg. 10 pbw of acetylene black, 1 pbw carbon fibres and 1 pbw of ethylene tetrafluoride resin. The separator comprises a non-woven cloth film of polypropylene. The thionyl chloride solution is prepd. by dissolving 1.5 mol/l of LiAlCl4.
Process for mfg. Pb accumulator electrodes comprising an inert, conducting collector surrounded by active material of Pb or a Pb cpd. with a partly reticular polymer where: A. An agent causing partial reticulation is added to a satd. aq. soln. of the polymer contg 5-20 wt.% catalyst, the novelty being the following steps: B. To soln. A at 50-100 degrees C is added 20-50 pts. wt. per pt. wt. of polymer, of a soluble Pt salt compatible with the polymer.    C. The soln. is cast in a mould contg. the collector at a temp. near the crystallisation pt. of the ternary system polymer/Pb salt/water. D. The mould is cooled, the cake removed and dipped in a satd. alkaline soln. of Pb(OH)2, then washed in cold water, dried at 20-60 degrees C, and compressed at 2-10 bars/cm2. The process gives pronounced redn. in electrode wt. and the process can be automated for mass prodn.
The water-absorbing cpd. consists of: 1 pbw of oxygen absorbing and reducing carbon; 0.5 to 4 pbw of a "low oxygen overvoltage matl." consisting of 1 of CuWO3, NiWO4, CoWO3, WS and WC, or of WC coated with 1-20 wt% Co; and a binding, non-wetting matl. including PTFE. A metal current collector is embedded in the compsn. in order to form a water absorbing layer; a water repelling layer is laminated onto the water absorbing layer.
Reinforced accumulator plates, such as tubular plates are mfd., by feeding an active mass contg. liq. into the porous covering on the plate when the covering or envelope is located on the conducting element of the plate. The amt. of liq. used causes the mass to be filtered out through the pores, to deposit a bed of active matl. in the covering, the bed being built up towards the feeder inlet, and the liq. flows through the walls of the covering during the build up of the bed. The slurry used pref. contains a ratio active mass:water between 0.4:1 and 2.4:1. A completely controllable mass prodn. process using a low viscosity slurry is provided by altering the pressure, various degrees of consolidation of the active mass can be consistently obtd.
Armoured plates for accumulators are mfd. by feeding an active mass into the porous sheath of a sheathed plate, when the sheath is positioned on the conductive element of the plate; in the form of an aq. sludge having a density, expressed as a turning amment value, when measured in a rotary vane viscosimeter, in the region of 0.83 to 8.3 m. g., at 20 degrees C. A pressure of &lt;1.05 kg/cm2 is applied until the sheath is filled with the mass, and then the pressure is raised to a new limit of not &gt;7 kg/cm2, before being detented. Gives fillings of uniform wt. and density throughout the plate.
In the prepn. of a cadmium negative electrode plate for a nickel-cadmium cell, a porous core sheet is fileld with a paste of a mixt of CdO active material, paste material such as polyvinylalcohol, and solvent. The active material is charged from 20 to 50% of the capacity and then pressed. An improved active material having excellent adhesive property may be obtained so that the active material is not peeled off during winding.
Alkaline battery having an improved separator contg. electrolyte, the separator comprises a sheet of a synthetic resin fibre, such as polyamide impregnated with porous inorganic powder. The self-discharge of the battery is greatly decreased.
A zinc alkaline electric battery has its negative electrode plate made of a material contg. small particles of zinc, 0.1-10 wt. % zinc oxide, alkaline electrolyte, 0.05-10 wt. % gelling material, and 0.1-20 wt. % inorganic oxide or hydroxide. The inorganic oxide or hydroxide may be a mixture of two or more inorganic oxides or hydroxides. The metal of the inorganic oxide or hydroxide may be barium, titanium, aluminium or zirconium, or a mixture of at least two of these metals. The gelling material is a metal salt of polyacrylic acid. The various materials are mixed to obtain a paste. The paste is used with a porous material sheet and a separating sheet to make up the negative electrode plate.
Galvani cell contg. an anode, a separator and a cathode depolarising body contg. MnO2, a carbonaceous electroconductive matl. and an electrolyte is improved in that the depolariser body contains as a binder 0.1-1.5 wt. % of a polyacrylamide having pref. a mol. wt. of 500,000-8,000,000. The cohesion of the depolariser body (cylindrical or flat) is improved without decreasing the electrical output (it can even be increased). so that the number of rejects is considerably reduced.
In a hydrazine-oxygen fuel cell using a porous asbestos membrane between the hydrazine-and the oxygen-electrodes, an ion-exchange matl. is embedded in the pores of the asbestos membrane. The wt. ratio asbestos to ion-exchange matl. is pref. 90:10-40:60, the asbestos membrane having a vol. porosity of 1-5% and being pref. 0.3-1.5 mm thick. The ion-exchange matl. is pref. sulphonated polystyrene, and the asbestos membrane pref. has a thicker edge zone impermeable to gas or electrolyte and contg. feeder channels. The asbestos membrane pref. forms the covering layer for the oxygen electrode. The cells are useful for low power output. The asbestos membrane reduces the chemical short circuit currents, and provides adequate transport of water to the oxygen electrode.
Catalyst electrodes for electrochemical processes, esp. in fule cells, are produced by (a) mixing the catalyst or its precursors with a synthetic resin, (b) moulding the mixt., and (c) heat treating the moulding, so that the synthetic resin is pyrolytically decomposed, and the precuros is converted into the catalyst. Mechanically stable electrodes are obtd. having a satisfactory electrical conductivity from powdered catalysts. Good resistance to high temps. and porosity can be controlled so that the catalyst activity can be fully utilised.
Porous sheet is made by spraying a liquid dispersion of an org. polymer through an electric field so that the polymer is ppted. as fibres which are collected on an electrode. The fibres are removed from the electrode and consolidated into matting. Esp. for mfr. of porous diaphragms for use in electrolytic rolls, fuel cells, etc. The spinning conditions and field strengths may be adjusted to vary and control the coarseness of the ppted. fibres and hence the porosity of the product matting. All the fibres are collected by the electrode. Pref. for mfg. fibres 0.1-25 mu, pref. 1-5 mu in dia. made predominantly of a fluorocarbon polymer, esp. PTFE. The fibres are ppted. from a pressure spinning soln. of viscosity 0.1-150, pref. 1-10 poises contg. 0.2-6% wt. of a supplementary polymer chosen from polyoxythylene, PVA, polyacrylamide, or polyvinylpyrrolidone.
A battery separator wettable by sulphuric acid is made from a non-wettable non-woven mat of polypropylene fibres by wetting it from one side only by a surfactant water soln. removing the water ot leave a deposit of surfactant by passing the mat through a counter-current hot air oven, heating the mat to above its softening point and finally compressing to a desired density. The soln. is at 60-170 degrees C and contains 0.2 to 1.0% by wt. of an anionic or a non-ionic surfactant. The surfactant is deposited inan amt. 0.3% to 1.0% by wt. based on the fibres and the final compression of the mat reduces it to avoid fraction of at least 0.4 Final compression may involve the provision of ribs upon the mat. The mat by virtue of its surfactant deposit is resistant to acid attack.
Ethylene and its mixts. with other alpha-olefins are copolymerised with butadiene or isoprene in aliphatic or aromatic hydrocarbon solvent at 20 to 120 degrees C and 1-30 atm. in the presence of a organo metallic complex catalyst. The latter is the reaction product of a titanium cpd. of formula- Ti(OR)4-nXn, (R is 2-15C hydrocarbyl; X is halo; n is 0-3) and aluminium trialkyl or alkylchloride in molar ratio 2:1-20:1 to produce a copolymer suitable for wheel rubber prodn.
A separator for an alkaline battery which is not oxidized by positive electrode mix or corroded by electrolyte, is made by irradiating a resin film (which is decomposed by light) to make it porous. An alkaline battery wherein said separator is employed cannot self-discharge, and has long life time.
The battery comprises a cathode, an anode, an electrolyte and a separator sepg. the cathode and the anode. The separator consists of a porous film of highly crystallised cellulose and has a high mechanical strength.
Mould for producing articles having a base with ribs upstanding therefrom, is in two parts relatively movable to a moulding position and to a position where a moulded article can be removed from the mould. One of the mould parts has channels to form the ribs on the moulded article and a stripper assembly has a frame with a number of stripper bars attached to the frame and extending in the bottom of the channels movable with frame relative the channels to engage the ends of the ribs of a moulded article to eject the article from the mould. Used for moulding a ribbed battery cover. Provides a simple effective stripper which removes the moulded article without any distortion.
Battery for watches and heating aids has anode and cathode materials in separated flanged plastics casings with the flanges sealed to one another, and metal outer casings secured to the plastics casings so as to be flush with the outer periphery of the flanges. Prior swaging of the metal casings with possible internal damage is avoided by the flanged joint and the outer battery surface is smooth to facilitate insertion. The battery can be easily shaped to fit a space and has longer leakage path for electrolyte.
A high energy density cell comprises (a) a positive electrode of Co2O3 and/or Co3O4, (b) a light metal negative electrode and (c) an electrolyte comprising an organic solvent from tetrahydrofuran, N-nitrosodimethylamine, dimethyl sulphite, propylene carbonate, butylrolactone, dimethyl carbonate, dimethoxyethane, acetonitrile and mixts. contg. dissolved soluble salts from perchlorates, hexafluorophosphates, tetrafluoroborates, tetrachloroaluminates and hexafluoroarsenates of light metals. The cells (Li/Co3O4) had an open circuit voltage of 3.5V which dropped rapidly to 1.1V and remained steady to the end of the discharge. Utilisation efficiency of the cathode was 85% at 0.52 ma/cm2 and 99% at 1.04 ma/cm2 and volumetric capacity of the Co3O4 depolariser was over 5.2Ahr/cm3, based on active material. The system did not exhibit gassing during storage or operation. The cell is esp. suitable for use in electric watches.
A coherent electrode for use in aq. electrolyte electrochemical devices comprises particulate MnO2 and particulate conductive material dispersed in a conductive polymeric binder consisting of colloidal conductive material having a surface area &lt;100 m2/g, as defined by the BET method using N2 absorption at 78K, and an electrolyte wettable polymer. The electrodes are thin, coherent and porous, providing high MnO2 utilisation, high discharge rates and long cycle life in rechangeable cells. The polymer is selected from acrylonitrile-butadiene-styrene polymer, epoxy resin, polymerised lower alkyl ester of acrylic or methacrylic acid, melamine-, urea- or phenol-formaldehyde resin, chlorinated polyether, polycarbonate, polysulphone, polystyrene, styrene-acrylonitrile copolymer, PVC vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol and styrene-butadiene copolymer and is esp. at least 1 wt. % mixt.
An anode assembly is prepd. by swelling an aq. polymer (I) latex with a water-misc. solvent (II), mixing the swollen latex with Xn dust, (I) being 0.5-5 wt. % on Zn; coating an electrically-conductive resin substrate with the mixt, then drying. The thin, flat anodes are used in cells and batteries for tape recorders etc. (I) holds the Zn dust together to form a stable mass but does not form a continuous film which would interfere with the opening of the cell.
Porous ethylene tetrafluoride resin matls. having homogeneous and dense distribution of extremely fine holes (for example, hole size &lt;1500 pref. 100-1000 A degrees) which are useful for diaphragm for sepn. of gases, for example, diluted gas, isotope gas, etc., diaphragm for electrolysis, diaphragm for battery, etc., are prepd. by extruding uncalcined ethylene tetrafluoride resin mixts. contg. liq. lubricants and moulding them by rolling, drawing the mouldings in an uncalcined state at least in the monoaxial direction, calcining the drawn mouldings at &gt;327 degrees C under conditions such that the mouldings may heat-shrink freely, and drawing the calcined matls. at least in the monoaxial direction.
Lead-acid, electric battery assembly consists of a container, pref. of GRP, and an insertable rack for holding the plates. The rack comprises spaced panels, pref. of polypropylene structural foam secured together by tie rods with tubular spacers, both pref. of polypropylene. The sides of the panels are vertically grooved to receive the plates by their edges. Contact bars at the bottoms of the panels support the weight of the plates and make electrical contact with them. Good flexibility is shown, such that plates of many different sizes and proportions can readily be accommodated by slight adaptation of the assembly.
An explosion-proof battery vent comprises a cup-shaped body with a tubular lower end for connection with a cell aperture of the battery, a centrally pierced horizontal plate near the top of the body, a ring-shaped disc of acid resistant porous material, serving as a flame barrier, attached to the bottom of the plate, and a lid spaced above the plate, leaving a space open to the atmosphere, gas entering the bottom of the body being directed to pass through the disc and plate before passing to the atmosphere.    Maintenance can be carried out without removing the flame-barrier. The barrier is less liable to clogging with dust.
A component assembly for use in electrochemical cells comprises first and second components coextensive with a and adhered to opposite faces at 1 plastic, nonconductive network contg. openings, with active or inactive material within the openings contacting the faces of the two components. Pref. the first component is a metal node, esp. from Zn, Zn-clad steel, Al, Pb, Cd, Mg, Fe and the second component is a moulded cathode of oxidic material, esp. from MnO2, PbO2, Ni oxyhydroxide, mercuric oxide, Ag oxide and inorganic metal halides. An electrolyte, esp. aq. KOH contacts the faces of anode and cathode through the openings in the plastic network. Two components of a thin, flat cell are secured in spaced apart relationship, the adhesive bond being strong enough to avoid components separating due to swelling or gas build up during storage or operation.
An Li-I cell comprises (a) an Li anode having an Li element and an anode current collector and (b) a cathode comprising an I element, a charge transfer complex of an organic donor component and a cathode current collector to the charge transfer complex. Excess I is maintained separate from the charge transfer complex, allowing the latter to be optimised for max. conductivity, avoiding permanently binding I in the complex, allowing the I content to be optimised without regard for conductivity.
The device is used in chemical sources of current employing oxygen from the ambient air as oxidising agent. To prevent the electrolyte from soaking through, 5-50 mg/cm2 of paste made from inert metal oxide mixed with an aqs. suspension of polyfluoroethylene resin (3 : 5 to 5 : 3 ratio by wt). is applied to the porous water-repellent plate before pressing in the metal mesh current tapping. Servicelife of these electrodes at room temp. is 3000-4500 hr.
A paste layer film for dry cells comprises a gelatiniser film layer, a water soluble polyvinyl alcohol film layer, and a methylcellulose film layer, the layers being laminated in turn.
The method of mfr. comprises (1) coating a soln. of titanium dioxide on a polypropylene thin film and drying to form composite layers of the polypropylene and titanium dioxide, (2) coating a soln. of polystyrene fine powder on the titanium dioxide layer and drying to form the separator of polypropyelene-titanium dioxide-polystyrene layers. The separator has a low electric resistance and high mechanical strength.
The electricd battery has several vertical metal spines secured to a common top bar and are each surrounded by active material enclosed in a tubular sheath of e.g. polyvinyl chloride. The sheath has a bottom cover which fits over the bottom end of the tubes and is shrunk to grip them, and a top cover which encloses the top bar and the tops of the tubes with an opening for a terminal lug and which is also shrunk to grip the bar and tube tops.
In the prodn. of non-woven fibrous matting by extrusion and entanglement of an array of extruded thermoplastic filaments, a non-ionic surfactant is injected into the molten matl. passing through the extrusion barrel. General, but esp. suitable for mfr. of accumulator separator screens weighing 10-500 g/m2 with a max. pore size of 40 mu and a porosity of 40%. Suitable for screens made of 2-8C polyolefins, polystyrene or polyamide matls., esp. polypropylene matting made from threads of 0.05-50 mu dia. Addn. of the surfactant during instead of prior to the extrusion process apparently allows the extrusion temp. to be reduced and improves the wettability of the prod. matting by aq. media such as battery electrolytes.
A non-woven fabric of olefine fibres is rendered more absorbant by impregnation with a copolymer derived from an alpha-olefine and a non-satd. alpha, beta, acid. The fabric is used as a separator in an accumulator. The absorbence of the olefine based fabric is considerably enhanced.
A dimensionally flexible, leak-proof, joint-free, hollow vent, having vent plugs for filling wells of a multiple cell battery, comprises a top member integrally moulded with a peripheral skirt member and a bottom member, the bottom member comprising vent plugs dimensioned to fit snugly into the filling wells to form a fluid-tight fit, each vent plug having a vent hole at the bottom, a flat region extending from the periphery of the bottom member towards the tops of the vent plugs, and a stress-distributing ring integrally attached to the flat region and the top of each vent plug.    USES -   For batteries in boats, motor home trailers and automobile engines.    ADVANTAGES -   One-piece construction requiring no assembly. Less risk of leakage due to absence of seams
An electrode structure for fuel cells is prepd. by (a) blending particles of noble metal black and 10 wt.% dry PTFE, based on total noble metal black and PTFE, and particles of soluble bulking agent in a liq. in which the bulking agent is insol., (b) filtering liq. from the blend, (c) rolling to form a sheet of fibrillated PTFE contg. noble metal black and bulking agent, and (d) removing the remaining liq. from the sheet.    ADVANTAGES -   The intermediate electrode structure formed is homogeneous, with uniformly distributed noble metal, enabling low loadings of 0.25-3 g/ft2 to be used. It is more easily handled than a similar structure without the bulking agent. The bulking agent is easily removed for use.
The cathode of a seawater battery comprising a metallic anode, cathode and a separator between them comprises a grid and an active material mix of Pb chloride and 1-10 (2-3) pts. wt. Pb oxide per 100 pts. wt. Pb chloride.    ADVANTAGES -   The battery is rapidly activated on immersion in seawater without sacrifice in electrical capacity, even after long storage and in adverse conditions of low temp. and heavy load. PREFERRED The active cathode material pref. also contains C black and polyfluoroethylene. The Pb oxide is PbO, PnO2 or a mixt. of PbO and lead with Pb forming 20-30% mixt.
A flux coating on an electrode is coated with a moisture proof film, which is formed by painting or spraying a solution comprising at least one resin selected from alkyd resin and polyurethane resin, solvent, hardener and putty oil in order to penetrate the solution into the flux, and by drying the coated electrode so as to harden the resin and to form a moisture proof film.    ADVANTAGE -   The coated electrode having a moisture proof film thereon can be stored for a long time.
A dry cell has a separator coated with a water soluble cellulose derivative contg. hydroxypropoxy groups using a solvent capable of dissolving part of the derivative. The percentage of hydroxypropoxy groups in the cellulose deriv. is in a range of 4-13%, preferably 7-10%. The solvent used includes a mixture of methanol and water, ethanol, methylene chloride, acetone, benzene, salicylaldehyde, tetrahydrofurfuryl alcohol, methyl cellosolve and methyl lactate.    ADVANTAGE -   The resulting dry cell has good preservation and improved processing property.
A dry cell incorporates an anode terminal cap formed on the upper portion of the carbon rod current collector. The anode cap is manufactured by coating a thermosetting type electro-conductive paint composed of carbon as electro-conductive material onto the inner portion of the cap and baked by heating. In the dry cell, the terminal cap protects from electrolyte creeping up porous carbon rod then prevents leaking of electrolyte from corroded cap. The thermosetting resin used may be epoxy-polyamide, phenol, epoxyphenyl and/or xylene resins. The terminal cap is made of iron or bronze plated with silver or nickel.
An organic substance having a m.pt. lower than the decomposition temperature is added to natural or synthetic graphite opt. mixed with carbon black (furnace black or acetylene black) and the mixture is blended together at the melting temperature of the organic substance and moulded and heated at 900-1500 degrees C for several tens of hours in the absence of oxygen and sintered to give carbon rod. A Leclanche type tubular dry cell made using the carbon rod has improved ability to release solution during or after discharge. The organic substance includes epoxy resin, phenol resin, furan resin and xylene resin.
Electric battery box is fabricated from non-corrodible sheet material to form a double-skinned open-topped box. The box is supported and restrained on the exposed faces by shuttering while a core of rigid plastic closed cell foam is cast into the space between the skins. The foamable compsn. is introduced through an inlet opening and space vented through an outlet opening.    USE -   The box is used for large batteries of open-stationary type e.g. of 2000-1500 ampere-hour capacity, suitable for telephone exchanges, stand-by and peak-load in railway signalling systems, power stations.    ADVANTAGES -   The boxes can be made wholly in plastic material without the aid of expensive moulds. The batteries can remain unattended for long periods.
Improved air-tight sealing is ensured by air-tight baking before assembly, sections of the cover and case coated with plastic. A think layer of alkali-resistant plastic is applied separately on the case and cover. Application of plastic, e.g. polyvinylbutyral, can be done by the vortex method in electrostatic field in 1-3 sec. The plastic layers are then baked at 220 degrees C for 4-5 mins. This produces a strong bond between metal and polymer. After the cell assembly the plastic layers are welded to each other, forming a continuous seam. The welding can be done at 100-150 degrees C directly, or by the diffusion method with wetting of the surfaces with alcohol, at 60-80 degrees C.
Liq. polyvinyl alcohol in water or electrolyte is reacted with boric radical, followed by gelation; a layer of this gel is inserted between depolariser and adhesive layer of dry battery. The battery has excellent charging ability, storage stability and liq. leak resistance.
A water-repellent layer and a catalyst layer are formed on one side of porous nickel substrate. The water-repellent layer contains as a main ingredient a water-repellent thermoplastic resin such as ethylene tetrafluoride-propylene hexafluoride copolymer resin and polyvinylidene resin. The catalyst layer contains as binder a water repellent thermoplastic resin. The structure is then heated at or above the m. pt. of the thermoplastic resin from the untreated side of the substrate. The resulting gas diffusion electrode can be used for a long period, the gas-liquid contact interface being stably maintained.
Method of making an electrode plate consisting of lead or lead alloy fibres comprises coating fibres of lead or alloy thereof with synthetic resin, weaving or knitting the coated fibres to form a mat-like member, removing part or the whole of the synthetic resin from the fibres, and converting exposed surfaces of the fibres into active material. The resin, e.g. PVC resin, reinforces the fibres of lead or its alloy, which are mechanically weak. The mat-like member thus obtained has uniform density, high tensile strength, long life and uniform expansion coefficient.
An electrolytic device includes metallic electrode in contact with polymer matl. which as been at least semi-cured by radiation and serves to retain electrolyte. Used esp. for wound or stacked foil type electrolytic capacitors, or possibly as battery cell. Harmful abrasive effect on the dielectric oxide film of the electrode, is eliminated e.g. in comparison with paper separator.    No possibility of environmental pollution arises in mfr., since radiation curing does not emit noxious gases.
Membranes with small pore size are obtd. by mixing the solns. comprising membrane-forming high molecular cpd. (A) and a solvent (B) with addn. of polyfunctional cpd. (C) which do not react with the (A) and (B), and forming membranes from the mixts., and then treating the membranes with the coagulating agents consisting of other polyfunctional cpds. (D) reacting with (C) and non-solvents of (A). The resulting porous membrane has net-like structure and is stable chemically and physically. It can be used as the filtration membranes for reverse osmosis, ultrafiltration and accurate filtration, diaphragm for battery and an ion-exchange membranes by introducing ion-exchange gps.
Lead acid accumulator plate and electrode with reduced weight without interfering unduly with the electrical and mechanical performance, are made up as a four layer sandwich symmetrical in its thickness dimension. The outer two active layers are of lead or lead oxide, the centre layer being a titanium matrix carrying titanium nitride and carbide of formula TiCxny (x + y = 1) in solid soln. form using ABS or polypropylene binding agent. Various methods are described for mfr. of the matrix including ion bombardment and chemical methods. The mean density of the electrode may be approx.
The cell of an alkaline accumulator consists of two membranes, enclosed on the periphery by an annular seal, which accept a gel material between them or are coated with a gel material. The gell material has anti-alkali and ionic conductivity properties. The membranes are made of a material permeable to ions (cellophane sheets) and the gel material consists of a synthetic or natural polymer (gelatine). This prevents any contact of the cellophane with the oxidant in the alkaline solution so that the cell output remains unaffected. The life of a cell is considerably lengthened.
Novel wettable polyolefin (esp. polypropylene) non-wovens are characterised in that the fibres are grafted with one or two monomers elected from acrylic acid, methacrylic acid and their esters with alkanols contg. one or more polar gps. (esp. 2-(N,N-diethylamino)-ethyl acrylate or 2-aminoethyl methacrylate). The non-wovens are useful as accumulator separators; the grafting makes the fibres sufficiently hydrophobic to be easily wetted by the battery electrolyte without affecting the porosity. The grafting process can be easily effected in aq. soln. without using organic solvents.
A pellet for absorbing hydrogen gas consists of a solid compound which will react with hydrogen, a catalyst for that reaction and a binder to retain those materials in a shaped body porous to hydrogen, the body being encased in a sheath which is permeable to hydrogen but not to liquid. Preferably the reactant is a metal oxide, the catalyst is a noble metal and the binder is a cement. The pellet is incorporated in a sealed battery to prevent development of dangerously high levels of pressure from unreacted hydrogen.
Nonwoven flat textile prod., esp. for battery separators consists of electrolyte-resistant thermoplastic fibres or threads, and is reinforced by point welding, the welded places forming 2-40 esp. 3-15% of the total surface of the prod. The prod. has excellent porosity as a result of the absence of binders, good filtering action, and performance as a battery separator; can be formed into a roll and has long operating life.
A polyvinylidene fluoride (I) is mixed with a cyclohexanone (II); they are heated at 90-145 degrees C to form a (II) soln. contg. 10-30 wt.% (I); the soln. is cooled and gelled; and (II) is removed. The prod. has high air and liq. permeability, and good porosity and hole size.
Cathode plate for nickel-cadmium alkali storage battery has a thin coating of polysaccharide or its deriv. (e.g. sodium carboxymethylcellulose, methylcellulose, etc), formed on the sintered cathode including active cadmium. Alternatively cathode is immersed in 0.01-1 % soln. of polysaccharide or its deriv. (after electrolytic formation in aqs. solution of caustic alkali), followed by drying. The process is simpler, cathodes are easier to handle and battery efficiency is improved.
Lead- or lead alloy-fibre coated with synthetic resin (e.g. polyvinylchloride resin, polypropylene resin, etc.) and the same uncoated are mixed and moulded under press. to a mat. Subsequently, part or all of the resin on the fibre is dissolved or fused to fix the entangled fibres, and the exposed fibre surface is activated as electrode. The strength of the electrode is increased without loss of merits of the lead- or lead alloy fibre.
A water activated lead battery is mfd. by inserting a pouch into a soln. inlet of a battery, the pouch consisting of e.g. thermoplastic polyethylene resin; introducing compressed air into the pouch to inflate it; injecting a condensed electrolyte into the inflated pouch through an opening of the pouch; and fusing the opening part of the pouch to the battery body. The amt. of condensed electrolyte to be injected into the battery can be increased. The specific gravity of the electrolyte can be decreased to 1.4.
A lead storage battery having long life during charging cycles comprises: an electroce plate made by subjecting fibres of lead or its alloy to powder treatment or dispersion treatment with water-repellent polymers of ethylene tetrafluoride, ethylene hexafluoride and polyfluoroolefin resins.
An electrode for an electrical cell is made by depositing a metallic layer (Pt) on a solid substrate at least part of which is non metallic and ionically conductive (silver rubidium iodide, collodion, acrylamide or regenerated cellulose), and forming directly on the metallic layer an active species permeable membrane (plastics film (PTFE or silicone rubber) &lt;10mu thick). The metal layer may be deposited by vacuum evaporation, sputtering or chemical deposition. The electrode is useful in polarographic, coulometric, fuel and voltaic half cells for monitoring fluids for major, minor or trace constituents which are active species e.g. partial pressures in air of industrial solvents such as methanol, ethanol or ketones may be monitored or atmospheric pollutants in concens. as low as 1m 108 or 109 may be detected. The electrode can be made by vacuum deposition processes and the membrane is thinner than in prior art electrodes so that higher signal to noise ratios are obtained and lower concens. of active species can be detected.
In the prepn. of a porous compacted self-supporting, non-woven mat of polyolefin fibres used as a battery separator, heated polyolefin is extruded through die nozzles into a gas stream to attenuate the extrudate into 1-10 mu diameter-fibres, collecting them as a 20-100 mil thick non-woven mat and then contacting the mat with an aq. surfactant compsn. (I) to render the mat wettable, the improvement comprises incorporating into (I), colloidal silica so that the mat remains wettable after washing for running water for 16 hr. After contacting with (I), the mat is dried and then compacted, the product having a thickness of 10-40 mil and a pore size of 10-40 mu. The battery separator retains its wettability in a storage battery for &gt;3 years.
Lead accumulator having long life and excellent rapid discharge characteristics has been provided. An electrode plate is obtained by mixing lead or lead alloy fibres, acid-resistant resin fibres such as polyethylene and polypropylene plated with lead and acid-resistant metal fibres such as Ti and Ta plated with lead and forming the mixture into a plate. Active material is formed on a surface of the electrode plate. Expansion breaking of the electrode plate and lowering of reactivity due to expansion of the electrode plate are prevented.
The separator for an alkaline battery is capable of good retention of alkaline electrolyte and has high affinity for alkaline electrolyte as a result of treatment with a surfactant. Synthetic fibre plate e.g. nylon, polypropylene or teflon is impregnated with a solution prepared by dissolving polyoxyethylene alkylamine type surfactant in a low b. pt. organic solvent e.g. methyl alcohol, ethyl alcohol or acetone. The impregnated synthetic fibre plate is dried rapidly at 60-80 degrees C. This separator can be made at low temp. and more rapidly. It has excellent liquid retaining capacity is uniformly treated with a surfactant.
Mesh is joined to a part of thermoplastic matl. such as A.B.S., polypropylene or nylon, by impressing the part with a tool which is shaped to raise up a rib on the surface by plastic flow from adjacent area. The mesh is pressed into the rib matl. by a second tool to effect a joint. Pref. the metal mesh and synthetic resin substrate define part of an air electrode of a metal-air battery cell.
An electrical energy storage battery comprises (a) a case, (b) at least two porous electrolyte containers within the case, contg. anode and cathode respectively, (c) a solid hydrogel, contg. enough electron transferring agent to render it conductive, between the containers, (d) a second solid hydrogel saturated with a cpd. from ZnCl2, ZnO, CdCl2 and CdO to render it conductive in the cathode container and (e) a third solid hydrogel saturated with a cpd. from Cr chloride, Cr oxide and alkali-metal-contg. chromate salts to render it conductive in the anode container. The battery uses inexpensive materials, is readily rechargeable and produces a high voltage while maintaining low current output, e.g. on discharge through 12 OMEGA a battery produced 2.40V, 240mA, at 0 min., 2.21V 172 mA at 120 min., .58V, 128mA at 270 min.
The parent patent described a forced circulation electrochemical generator having several reaction elements, each with a wall sepg. inner and outer regions connected together so that an alkaline soln. contg. a suspended metal can circulate in the inner regions and an oxidising gas can be circulated through the outer regions, the dividing walls comprising from the inside outwards (1) a porous, hydrophobic, insulating unalterable sepn., impermeable to the powdered metal, (2) an active porous, electron conductive which permits a redn. reaction, at its core, (c) a water repellant, layer, porous and unalterable, a positive metal permeable collector in contact with the active layer and a negative collector in the interior space, the generator being in tube form and having a closed curve section, the interior space being inside the tube and the exterior space outside it. In the patent of addn., the active porous layer comprises 70-20% activated charcoal, 5-40% hydrophobic agent and 20-70% nickel powder. The electrical output of the generator does not suffer perturbations due to carbonatation of the electrolyte.
A fabric reinforced elastomeric container is made by applying a fluorocarbon elastomer inner layer to a former, applying a solvent solution of a fluorocarbon elastomer over the inner layer, pressing at least one layer of fabric onto the liquid layer to cause the liquid to strike through the fabric, applying at least one further coat of fluorocarbon elastomer over the fabric, curing the assembly thus formed and finally removing the former. Formers are preferably of plaster of Paris and are removable by soaking with water. All layers may be applied by spraying, dipping, brushing or the like. A bubble-free, leak-free container is suitable for use as a high temperature resistant fuel container.
An electrically conductive substrate for an electrode support in a fuel cell is mfd. by (a) blending C with dry powdered PTFE in a lubricant, the PTFE being 6-32 wt. % C + PTFE, (b) filtering lubricant from the blend, (c) rolling the filfered mixt. to reduce the thickness and form a sheet of fibrillated PTFE contng. C and lubricant, and (d) removing the rest of the lubricant. The porous graphitic support allows reasonable rates of gas access to the catalyst, has good electrical and thermal conductivity and is resistant to corrosion by the electrolytes. It is much less expensive than the few metals suitable as supports for the severe conditions encountered in fuel cells.
A gas electrode contng. a hydrophilic layer comprises a composite providing a gas-liq. interface and contng. an O absorption/redn. electrocatalyst from CaMnO3 and Ca1-X-zMnO3:Nax, Yz (where x, z are 0.05-0.40), and a metal current collector. The electrocatalyst is low cost material, is stable in KOH, has low resistivity and contact resistance with the metal and provides high capacity over long charge/discharge cycles. It is used in place of conventional C catalyst, and reduces or eliminates the need for other catalysts, e.g. Ag, WC.
Dry cell is prepd. by (1) coating one surface of a separator with a paste composed of a substance such as starch and polyalkylene glycol and not contg. salts, (2) drying the paste, and 3) disposing the separator between a zone anode and a cathode mixt.
Fibre sheets prepd. by mix-fibre spinning of 60-99.5 thermally stable (nonmeltin) phenolic resin fibres and 0.5-40% thermoplastic resin fibres (25 mu dia.) selected from polyester, polyolefin, or polyacrylic fibres, were hot-pressed at 60-200 degrees to give Pb battery separators having continuous pores. The separators have good acid and oxidn. resistance, and exhibit good H2SO4 permeability. The separator sheets can be made very thin and thus increase the battery capacity.
In Fe-Ni secondary batteries, the Ni cathodes, the Fe anodes, and the composite separators made of porous cryst. polypropylene film and unwoven polypropylene cloth were arranged so that the cathodes and anodes were in contact with the unwoven-cloth and porous cryst.-film sides of the separators, resp. The arrangement improves discharge properties (high power output) of the battery, and also prevents the accumulation of gases generated at the anodes.
CM-cellulose powder is dispersed in 45% KOH, H2O is added until the CM-cellulose is dissolved, and amalgamated Zn powder is dispersed in the resulting paste-like electrolyte to give Zn anode mix. for alk. batteries. Opt., H2O addn. is discontinued when CM-cellulose is partly dissolved and the mixt. is gelled by heating and subsequently cooling. The dispersing of the CM cellulose in conc. KOH with subsequent diln. makes the soln. of CM cellulose simpler than dissolving CM-cellulose directly in 30-40% KOH suitable for the alk. battery electrolyte, and hence the prepn. of self-supporting anode mix becomes simpler. Thus, CM cellulose (polymn. degree 120,000, esterification degree 0.64) 10 was dispersed in aq. 45% KOH 120, H2O 20 g was added to the mixt. to give a paste-like electrolyte (38.5% KOH, CO-cellulose dissolved), and an appropriate amt. of 6%-amalgamated Zn (30-180 mesh) was dispersed in the paste to give a self-supporting Zn anode mix.
Ni-Zn alk. storage batteries consist of (1) a cathode employing Ni oxide as the active material, (2) an anode using Zn as the active material and having a discharge capacity larger than that of the cathode, and (3) an alk. electrolyte with OH- concn. 5-7M and 1.9-2.0 ml/A-hr theor. discharge capacity of anode, and (4) a gas catalyst. When the gas catalyst is used, localized discharge at the anode is eliminated and the battery can be sealed.
Sealed Ni-Zn storage batteries are obtd. by (1) placing a Ni cathode in contact with a Ni or Ni-plated vessel, (2) filling the vessel with an electrolyte consisting of 4-6M KOH or a mixt. of KOH and LiOH, and (3) using a catalytic gas electrode. These batteries have a long service life high energy d., and a low self-discharging tendency.
An electric pile battery, comprises a stack of electrodes and separators with spaces between neighbouring electrodes of opposite polarity, the spaces being closed at two parts of the periphery and open at two opposite parts to provide electrolyte inlet and outlet openings, one or each opening having a strip of a cement extending along the length of the battery across the edges of adjacent openings of a number of cells, and bulging into the openings to prevent their closure due to distortion of the sheets. Used as a sea-water battery. Prevents blocking of the water inlets and outlets due to plate distortion; facilitatetes equalization of flow through cells; does not complicate assembly.
In a lead acid accumulator using porous sheaths permeable to electrolyte surrounding the leads and packed with partly active material comprising PbO, H2SO4 and sufficient water to reduce the viscosity, the sheaths are filled with paste by injecting under pressure after the sheaths have been partially or completely conditioned with a material which fills and partly or completely covers the pores, and the permeability to electrolyte is reestablished (in)directly. The conditioning material is pref. a film former such as 4% CMC, PVA etc. which blocks the pores during filling and is subsequently removed with a solvent. Active paste is retained across the pore surfaces during pressure injection and is not carried away with the excess water.
An electrode material, suitable for use as positive electrode in an alkali cell, in which the negative electrode material is mainly ZN, comprises 100 (wt.) pts. NiO and 10-90 pts. MnO2, electrical conductor and binder. It can also contain 1.5-10% CoO or Bi2O3 or 0.1-5% Li cations. The conductor can be acetylene black, graphite, fine particles of Ag or Ni or a fluorocarbon, whilst the binder pref. is Portland cement, a thermoplastic resin which is resistant to alkaline media or a polyfluoroalkene. This electrode improves the cell capacity under high discharge loads, esp. at low temp., and gives a higher useful voltage and flatter discharge curve than usual for alkali-NiO-Zn cells.
The separator is obtd. by impregnating a sheet of separator paper with H3BO or borate soln., and coating it with aq. poly(vinl alc.) by using a gravure roller to produce a noncontinous nouniform poly(vinyl alc.) surface film. The separator takes up readily the electrolyte during battery manu. and is amenable to com. prodn.
CdS-base anode active substance and elec. conductive substance are mixed with a soln. consisting of H2O, H2O-miscible org. solvent, and an appropriate binder to give a paste-like mixt., which is coated on an alkali-resistant metal electrode support to give a paste-type Cd anode. The addn. of H2O-miscible org. solvent delays the reaction of CdS with H2O, and hence prevents premature hardening of the paste, and also maintains the mixt. soft even after H2O is evapd., and hence prevents the loss of active substance or shrinking of the paste.
Alkaline battery separator papers of u nwoven cloths having bulk density 0.10-0.18 g./cm3 and consisting of 70-90% poly vinyl alcohol fibres which are spun in alkaline soln. and hot stretched, and 5-30% soluble polyvinyl alcohol fibre-type binder, exhibit excellent alkalien electrolyte permeability and absorption capacity. In an example, polyvinyl alcohol having average polymsn. degree 1725 and average sapon. degree 98.8 mole-% was dissolved in H2O at &gt;90 degrees to give an 18% soln. which was spun into aq.NaOH (310 g./l.), the resulting fibre was hot stretched to 1 denier and cut in 3 mm. length. Separately the polyvinyl alcohol soln. was spun into NaSO4 soln., and thermally stretched to give 2 denier fibres, easily soluble in hot H2O. The former fibres 8 and the latter ones 20% were mixed and made into paper by the wet method. The paper exhibited excellent KOH soln. permeability and absorption capacity.
Cathode for a battery cell using an organic electrolyte comprise a current collector made of a gp. IVb, Vb or VIb metal esp. Ti, Ta, To or W and an active cathode material selected from V2O5, ahd chromates and bichromates of Ag, Hg, Cu, Pb, Fe, Co, Ni, Tl or Bi. The current collector is welded to a tongue and the weld region is covered with a film of polyolefin (polyethylene) and hot sealed to protect it against corrosion. The cathode is used in high energy density cells such as Li/V2O5, Li/(bi)chromate cells. Local corrosion of the join is reduced or retarded increasing the life of the cell. Storage life can be increased.
The plug has a polypropylene outer case which contains a funnel shaped exit from the battery and feeds a catalyst plate of asbestos fibres, treated such that it is hydrophobic and connected thermally to the steel or synthetic top cover of th eplug. The lower side of the catalyst support plate is impregnated with a hydrophobic agent and antimony hydride. Heat generated in this recombination process is conducted away sufficiently rapidly to avoid vaporisation of the water.
An electrochemical cell electrode, comprising hydrophobically-bonded, inert porous conductive particles supported on a substrate, is catalysted by (a) contacting the bonded particles with an electrolyte, (b) applying a non-alternating potential between substrate and electrolyte to increase the rate at which electrolyte fills the porous particles, (c) introducing a sol. catalyst-contg. cpd. into the electrolyte and (d) depositing insol. catalyst from the soln. onto the conducting particles. Impregnation time is reduced e.g. from 50-500 hr. to 15 min., and catalyst is deposited only where it can participate in the reaction.
Title electrode, which may be used in low temp. H2/O2 fuel cells operated at low pressure gradients and of lower wt., are prepared by adding up to 50% (by wt.) polyfuoroethylene resin to active metal catalytic suspn. which then is applied to porous substrate (e.g. from leaching Ni-Al fused materials) before heating in air at 230-260 degrees C, and then treating in a reducing atmos. (e.g. H2) at 230-250 degrees C.
Al fuel cell comprises a cell reaction chamber having a cathode and an anode collector, an electrolyte passageway communicating with the cell reaction chamber, and powdered Al anode active material injected into the electrolyte passageway, and coated with PVA or polyvinyl butyral which is chemically and soluble in the electrolyte. Al hydroxide is used as the electrolyte.
The anode is prepd. by coating a support with a binder contg. a water-soluble carbohydrate and an electrode-active mass, and leaching out the water-soluble carbohydrate. The method is simple and yields electrodes of high quality. In an example, a porous, Ni-plated, unwoven nylon fabric was coated with a paste contg. CdO (10 pts.) HOCH2CH2OH (1 pt.) dextrose (1 pt), and H2O (3.3 pts.) and rolled to force the paste in the pores of the support. After drying, the coated support was electrolysed in an alkaline soln. to reduce CdO to Cd. It was then washed with H2O to remove the alkali and water soluble dextrose giving a Ni-Cd battery anode.
A hydrophobic polymer matrix having preselected wettable characteristics comprises a continuous phase of sintered fluorocarbon polymeric material having a series of integral interconnecting pores and a discontinuous colloidal mineral phase deposited in or at the surfaces of the pores, the mineral phase being uniformly distributed from one major surface to the other. The polymers matrices are used as filters, separators, diaphragms, etc. and particularly as porous barriers, supports in electrode construction, or matrices for retaining an electrolyte for use in an electrochemical cell, esp. a fuel cell. The matrix has good mechanical strength, high porosity, selective wetting characteristics and excellent stability to chemical attack by electroyltes.
An immobilised electrolyte paste for a Pb-acid storage battery comprises 1.5-4.0 pts. H2SO4 of s.g. 1.050-1.350, and 1 pt. org. microparticles that are inert to H2SO4 and have a particle dia. of 0.1 - 3(0.2-1) mu. The particles immobilise the electrolyte sufficiently to prevent accidental spilla ge, but leave it with sufficient fluidity to recontact the electrode after forming and conditioning the battery plates, so the same electrolyte can be used throughout. The particles do not react with or contaminate the electrolyte, are safe to handle and reduce water loss by evapn.
An injection mould for making a partitioned container such as a battery casing comprises relatively reciprocable upper and lower mould halves. The upper half comprises a base member, four widewall members slidable along sloping guideways, and a first set of partition defining cores located within the sidewalls. The lower half also carries a second set of cores cooperating with the first set. A stripper ring is located about the cores of the upper mould half and an injector is carried by the lower mould half. Mechanical interlock means are provided so that when the mould halves are open the lower half pulls the sidewalls downwardly along the guideways and thus out of contact with the moulded container. At the same time the sidewalls pull down the stripper ring to push the moulded container off the first set of cores. Further movement causes the lower mould half to release the sidewalls and the container moves down with the lower half until an ejection plate causes the ejector to push the container free of the lower half. Mechanical interlocking which is more simple than the prior are hydraulic interlock devices is obtd.
The Zn anodes are characterized by the presence of a polyethyleneimine near the Zn active substance, but not in the electrolyte. The polyethyleneimine prevents the electro deposition of Zn on the anode from the electrolyte zincate ions during the battery charging, and improves the battery lifetime. In an example, ZnO 80, Zn powder 20, and 10% polyethyleneimine aq. soln. 30 parts were kneaded well and coated on Ni screen. The coated Ni screen was electrolytically reduced in 7N KOH to give a Zn anode having the polyethyleneimine dispersed in the active and porous Zn mass. A battery contg. this anode, an O-diffusion type cathode, and ZnO-contg. 7N KOH electrolyte had an excellent service lifetime.
CMC salts with av. substitution degree d 0.8 are used as the gelation agents. Only a small amt. of gelation agent is required resulting in increased amt. of electrode mix and increased discharge capacity of batteries. Thus 3.6% CM cellulose Na salt with d = 0.8 was added to the anode mix. contg. amalgamated Zn powder and NaOH-zincate electrolyte. The mix was incorporated in a Hg battery having a cathode mix contg. HgO and graphite. The battery had good discharge capacity and good storage stability.
A battery separator disposed between anode and cathode in the electrolyte of an electrolytic cell comprises (a) a hydrophobic microporous film having a lower bulk density than the corresponding non-porous precursor film, a crystallinity &gt;30%, an average pore size of 100-12,000 A a surface area of 2-200 m.2/g., and a void vol. of 20-45%, and (b) a surfactant coating the film, comprising 2-20 wt.% uncoated film of polyoxyethylene polymethyl siloxane or a mixt. of this with an imidazoline tertiary amine. The surfactant provides the necessary 'instant wettability', for a separator film, unlike conventional imidazoline surfactant which, when used alone, require long periods for electrolyte penetration.
Primary cell construction with high valency metal halide cathode and electrolyte constituted by alkali metal halides solution in anhydrous hydrofluoric acid has an improved characteristic and increased life by the use of lithium hydride anode. The cell consists of hermetically sealed cylindrical nickel case lined with cathodic material made of porous nickel filled with active mass of vanadium or niobium fluoride. Central anode consists of nickel base filled with lithium hydride. The electrolyte is an equimolar soln. of LiH and HF. Output terminal is insulated by PTFE sealing grommet.
A liquid -tight lead storage battery comprises an electrode plate assembly block composed of anode and cathode plates embedded in thermoplastic resin, such as polyethylene, polypropylene, vinyl chloride or ABS, contg. hydrosilicate gell powder which is impregnated with an electrolyte, The ratio of the height of the electrode plate to that of the resin block is 2:1-1:2.
Lithium, sodium, magnesium and aluminium are used as light metal for an anode. The organic electrolyte is prepd. by dissolving lithium perchlorate in an organic solvent such as propylene carbonate and gamma-butyrolactone. Metal halide such as nickel chloride and copper fluoride, and solid fluoro carbon are used as active material for the cathode.
A process for producing a microporous material is claimed, in which a liquid mixture consisting of a synthetic resin, an organic solvent for the synthetic resin, a non-solvent liquid and 4-methyl-2,6-di.tertiary-butyl-phenol is poured onto a surface of porous solid plate. The resulting coated plate is dipped into an extracting solution able to dissolve the 4-methyl-2,6-di-tertiary-butyl-phenol. The desired microporous material is then obtained by removing the resulting coating from the porous solid plate.    USE -   The microporous material can be used as a separator plate for lead batteries. (4 pp). (Delayed: Issued in Week X12).
A mercaptocarboxylic acid is added to the battery alk. soln. to inhibit corrosion of Zn. Gas formation in the battery is thus prevented and battery performance is improved. In an example, a cathode mixt. of MnO2 and graphte was moistened with 5% KOH and packed in a cylindrical can. The hollow can portion was filled with a Zn-electrolyte paste obtained by blending Zn powder and CM-cellulose with an electrolyte obtained by adding 0.01% mercaptopropionic acid to 30% KOH, a separator being placed between the depolarizer and the Zn paste. The battery showed, immediately following assembly, an open-circuit voltage 1.56 V a short-circuit current 1.20 A. The resp. values on storage for 6 months at 45 degrees were 1.52 V and 1.0 A, it required 7.9 hr to give a terminal voltage 0.9 V when discharged across a 4 resistor. These values were comparable to batteries using a conventional Zn electrode from toxic Zn amalgam powder.
Parent patent described design of an accumulator casing comprising a narrow, deep open topped moulding closed by a long narrow lid from which the electrodes and their terminals were supported. The addn. describes casing of similar shape made by assembling a shallow dish and a cover which becomes one of the two major vertical faces when the casing is in its use position. The terminals are fitted through holes in the upper panel, the panel being an integral sidewall of the tray half of the body as originally prefabricated. The tray component has a peripheral flange for making a welded joint with the flat cover. The edge panels of the body other than two panels supporting the terminals are not flat but have a shallow 'V' or positively dihedral cross section to sustain the cell alignment if and when the major side panels of the casing are flexed. The body mouldings are made of polypropylene. Requires less expensive tools and less material drawndown to make the body components than the original design. Also easier to install the cell plates.
An elastomer based on a peroxide-crosslinked EP- or EPDM rubber blended with a polyolefin is used in mfr. of a sealing frame body(gaskets) in electrolytic cells contg. strong acid, esp. in fuel cells. The matl. combines stability to strong acids with thermal stability.
Battery has a number of horizontally mounted plates each formed of a metallic grid and a paste applied to it, the grid being 0.018 to 0.022 inches thick and the plate 0.023 to 0.027 inches thick. The plates are mounted in a case having spaces above and below the plates with an electrolyte flowing through the plates from one space to the other. A passage is provided between the upper and lower spaces in a region separated from that occupied by the plates, a one way valve being provided to prevent downward movement of the electrolyte in the passage. A ir is (intermittently) introduced into the lowermost region to move the electrolyte from the lower region to the upper region through the passage. The device is a compact power source for an electric vehicle, the waste prods. from the plates are continually flushed away from the plates by circulation of the electrolyte through the plates.
A non-aq. secondary battery having a Li negative electrode, a positive electrode and microporus separators has an electrolyte consisting of a solvent, 0.01-2.0 Li salt from LiI, and LiClO4, and 1-5 wt.% tetraglyme and 0.01-0.6 M tetrabutylammonium iodide as dopants. The additive improves recycle characteristics.
Dry cell comprises an electrolyte soln. having ZnCl2 concn. of 16 to 28 wt%, NH4Cl concn. of 7 to 2 wt% and total electrolyte concn. &lt;30 wt%, and a paste consisting of a first paste matl. and a second paste matl., the first paste matl. consisting of methylcellulose, carboxymethylcellulose, sodium al nate, etc. which gels at a relatively low temp., and the second paste matl. consisting of corn starch, water-insol. polyvinyl alcohol, etc., which gels at a relatively high temp.
The anodes are obtd. by stirring powd. Zn into a gelled electrolyte and degassing under reduced press. Highly uniform high-d. gel-type Zn anodes can be otd. In an example, a gelled electrolyte was obtd. by mixing in slowly a soln. contg. H2O 28, KOH 22 and ZnO 4 pts. to a mixt. of CM-cellulose 1 in H2O 10 pts.    On adding powd. Zn 80 and Hg 6 pts. to the gelled electrolyte, a gel-type amalgamated-Zn anode was obtd. The anode was degassed at 10 torr for 20 min. The resp. anode d. before and after degassing was 2.2 and 2.8g/ml. A D-size battery was assembled with the anode of this invention contg. is approx 7% amalgamated Zn, a Ni plated metallic cathode container, a MnO2-based cathode, unwoven vinylon separator, a brass anode current collector, a plastic packing material, a metallic anode terminal, and a Zn-plated Fe outermost shell. After storage for 3 months at 60 degrees, the battery could be continuously discharged at 20 degrees across a 4 OMEGA load for 27.2 plus-or-minus 1.0 hr. until a final voltage of 0.9 V was reached. In contrast, a battery with a conventional anode and stored under the same conditions showed a drop in voltage to 0.9 V in 24.5 plus-or-minus 2.1 hr.
The battery comprises a light metal anode, a cathode, and an inorg. electrolyte dissolved in a mixed (gamma-butyrolactone-valerolactone) solvent. The battery has good low-temp. discharge characteristics. In an example, a cathode was made by pressing (1 ton/cm2) on a Ni screen collector a paste obtd. by mixing in a 100:7:10 ratio a fluorinated graphite acetylene black, and a fluorinated resin. A battery was assembled by using this cathode, a Li-coated Ni screen, and 1M LiBF4 in mixed (1:1 vol. ratio) lactones. After 80 hr. of discharging through a 150 OMEGA resistance at -10 degrees, the terminal voltage of this battery was higher (0.1-0.2V) than that of a similar battery contg. 1M LiBF4 LiBF4 in gamma-butyrolactone or valerolactone alone.
The Cd anode is obtd. by coating a porous substrate with a paste obtd. by blending an org. soln. of polyethylene oxide with an active material based on CdO and drying. The anode canbe prepd. readily, it ha superior performance, and when used in a battery, low gas evolution and large capacity. In an example, 2g. polyethylene oxide was dissolved in 100ml. HOCH2CH2OH. A 4:1 mixt. of CdO and Ni 300g. was blended with the above soln. 80ml., coated on a Ni screen, dried, and formed. A battery assembled with those anode and a sintered Ni cathode showed good discharge characteristics (5-hr. discharge) and large capacity when compared to a battery contg. a sintered anode and a sintered cathode.
The battery comprise a light metal anode, a fluorinated graphite cathode, and an electrolyte consisting of a soln. of an inorg. electrolyte in a mixed propylene carbonate or gamma-butyrolactone and Me2SO solvent. The use rate of the cathode-active material and the energy d. of the battery are large. In an example, the cathode was obtd. by pressing a (10:07:10) mixt. of solid fluorinated graphite, electroconductive acetylene black, and poly(tetrafluoroethylene) against a Ni screen from both sides. A battery was assembled by using this cathode, an anode prepd. by pressing a Ni screen against a Li sheet, and an unwoven polypropylene fabric separator. The battery was filled with a 1M LiBF4 in a 1:1 mixt. of propylene carbonate and Me2SO. This battery had a larger voltage than a battery using a 1M LiBF4 in propylene carbonate alone. Its discharge characteristics were also superior.
The battery comprises a Mg anode, a fluorinated graphite cathode, and an inorg. electrolyte dissolved in an org. amide solvent. In an example, the cathode was prepd. by adding a fluorocarbon resin binder to a 10:0.7 mixt. of fluorinated graphite and acetylene black and pressing (1 ton/cm2) the resultant paste on a Ni expanded metal current collector. A battery was assembled by using this cathode, an anode of an acid-washed Mg sheet with a Ni-wire current collector spot-welded to it, a polypropylene unwoven fabric separator, and a 1 M LiClO4-DMF electrolyte. The resp. open-circuit voltages of this battery and a conventional one contg. LiClO4-propylene carbonate were 1.82 and 1.45 V. Moreover, the battery of the invention showed more stable discharge characteristics.
The battery comprises a Mg anode, a fluorinated graphite cathode, and an inorg. electrolyte in a nitrile solvent. In an example, fluorinated graphite and acetylene black were mixed in a 10:0.7 ratio, stirred with the addn. of poly(tetrafluoroethylene) binder, and press moulded (1 ton/cm2) on a Ni expanded metal collector electrode (area 4cm2) to give a cathode. A battery was assembled by using this cathode, an acid-washed Mg plate anode, a polypropylene unwoven fabric separator, and a 1M LiAlCl4-MeCN electrolyte. The open-circuit voltage of this battery was 1.80 V and its 50-hr. discharge-rate curve was flat for a longer time than for a conventional battery contg. a 1 M LiClO4-propylene carbonate electrolyte. The limiting anode c. ds. of improved and conventional batteries were 170 and 20 mA/cm2, resp.
The cell uses an anode obtd. by bonding a high-purity Fe powder with a binder to a current collector, a cathode, and an alkali electrolyte. These cells are free of toxic Hg and Cd. In an example, a cell was assembled by using a com. MnO2 cathode, an anode obtd. by coating inner walls of a cylindric Fe vessel with an aq. paste contg. powd. Fe 10, produced by reducing basic Fe oxide in H at 820 degrees, and Me cellulose 0.5 pts. and drying at 60 degrees. The 10-hr. rate discharge capacity of the cell (final voltage 0.6 V) was initially 3.5, after 1 month 3.5, and after 1 year 3.3 A-hr. The resp. values for a cell using an anode prepd. with com. Fe powder were 3.1, 2.5, and 1.2 A-hr.
The battery of increased electrode utilisation rate and improved discharge characteristics comprises a Mg anode, a graphite fluoride cathode and an org. electrolyte contg. an inorg. solute in a mixed org. solvent based on amides and propylene carbonate or gamma-butyrolactone. In an example, a cathode was formed by pressing (1 ton/cm2) on an expanded Ni sheet current collector a paste obtd. by mixing (100:70) a fluorinated graphite with acetylene black conductor, and adding a hexafluoropropylene-tetrafluoroethylene polymer binder. An anode was prepd. by dipping a Mg sheet in dil. HCl for 1-2 sec. washing to remove the surface oxide layer, and spot-welding a Ni wire current collector. The battery was assembled by placing an unwoven polypropylene fabric separator between the electrodes and filling it with a soln. contg. 0.5 mole LiAlCl4/l. of a 1:1 (vol. ratio) DMF gamma-butyrolactone mixed solvent. The open-circuit voltage of this battery was 1.85V vs. 1.45V for a conventional battery using a 1M LiClO4 in propylene carbonate. On continuous discharging for 50 hr., the terminal voltage remained high and const. for &lt; is approx. 40 hr. In contrast, the conventional battery showed a lower terminal voltage which was relatively const. for &lt; is approx. 30 hr.
A mixt. of Raney Ni powder with Pt black and/or Pd black is hardened with synthetic resin binder to give a gas-diffusion electrode for a fuel cell. The addn. of Pt black or Pd black prevents the degrdn. of electrode owing to the formation of Ni(OH)2 or NiO, and hence increases the service life of the battery. In an example, Raney Ni powder 250g. was stabilised by oxidn. treatment, then Pt black 10g. and appropriate amt. of poly(tetrafluoroethylene) resin were added and moulded into the desired shape to give a gas-diffusion elect rode, which exhibited better electrode characteristics than the conventional ones.
The electrodes are prepd. by press-adhering 3 layers: Ag powder (5mu particle size) layer contg. 1-13% poly(tetrafluoroethylene) (I), a Raney-Ag (60mu particle size) layer contg. 6-20 (I) and a Ni powder layer contg. 13-50% (I). The 1st layer prevents gas leakage into the electrolyte chamber, the Raney-Ag layer acts as the catalyst layer for the gas-liq. reaction, and the Ni-base layer prevents electrolyte leakage into the gas chamber.
Poly(tetrafluoroethylene) (I) and poly(vinylidene fluoride) (II) are added as binders to an electrode-forming compsn., the compsn. is coated on a porous substrate, and the coated substrate is heat treated at a temp. between m.pt. of (II) and m.pt. of (I) to give a fuel-cell electrode. The binder exhibits good adhesion characteristics without degrading the catalysts and active C, and the electrodes prepd. by using the binder retains good gas permeability, and hence the method is useful for prodn. of gas-diffusion electrodes for fuel cells.
Polycationic polymers are added to the alk. electrolyte of a secondary battery with a Zn anode active mass whose charging is based on solid-phase electrolytic redn. of ZnO, and the battery is charged initially at a potential less neg. than the electrolytic deposition potential of the dissolved Zn. The addn. of polycationic polymers makes the Zn deposition potential more neg., and hence the charging of the battery without Zn deposition becomes possible, resulting in longer service life of the battery.
SH-Carbazole as a Zn corrosion inhibitor to the alk. electrolyte is reported for Zn-alk. batteries having Zn as anode active mass and caustic alkali as electrolyte. The carbazole prevents soln. of Zn and hence prevents the H formation in the cell. In an example, Zn powder, CM-cellulose, and an electrolyte contg. KOH 30 and carbazole 0.05% were kneaded to give an anode mix which was filled in a battery having MnO2-graphite-KOH soln. cathode mix; the open-circuit terminal voltage and closed-circuit voltage of the battery being 1.56 V and 11.5m V, resp. The resp. values after 6-month storage at 45 degrees were 1.52 V and 7.0mV. These values were comparable with those obtained by using amalgamated Zn as the anode active mass.
A cation-selective electrode has a membrane prepd. by dispersing hydrated Sb oxide in an inert matrix. The electrode exhibits good selectivity towards monovalent cations such as Na+, K+, and NH4+. In an example, is approx. 3 ml of H2O was added to 25 ml SbCl5, the mixt. was then added slowly to 1 l. H2O to ppt. hydrated Sb oxide which was washed, dried, and crushed. The hydrated Sb oxide powder was then dispersed in a soln. consisting of poly(vinyl chloride), dioctyl phthalate (a plasticizer), and THF. The resulting dispersion was coated on an appropriate substrate, and the dried film was peeled from the substrate to give a membrane contg. 30-60 wt. % hydrated Sb oxide. The diaphragm was then attached to the bottom of a tube, the tube was partially filled with 0.1N KCl soln., and a SCE was placed in the soln. to give cation-selective electrode. The potential of the ion selective electrode measured vs. a calomel electrode was linearly related to cation concn. in the sample soln. within the range 105-101M.
In an Zn alk. secondary battery in which an electrolyte is kept in the fine pores of the cathode, anode, and separator, the discharge capacity of the cathode is lowered below that of the anode, the O evolved at the cathode during charging is disposed of at the anode, the anode surface is made water repellent, and the cocn. of the alk. electrolyte is kept at 3-20%. By smooth gas removal at the anode, safe alk. Zn batteries are obtd. In conventional Zn alk. secondary batteries with rapid O evolution and without O removal, explosions are possible. By making the anode water repellent, a thin electrolytic layer is formed on its surface with the resultant shortening of the O diffusion length and smooth removal of O at the anode.
A polymer having alpha-methyleneglutaric anhydride gps. is added as a particle-forming agent to a mixt. consisting of a depolariser such as MnOi and elec. conductive material such as graphite flakes and acetylene black. The resulting mixt. particles are compacted to give a cathode mix for an alk. battery. The polymer has excellent particle forming props. as well as good resistance to the depolariser (oxidn. by depolariser) and the electrolyte.
An alkaline cell electrode is made by pressing at 1/2-3t./sq. cm. a dry powder mixture of AgO and P.T.F.E. (1-10% wt.). The powder mixture is pressed with or without a supporting skeleton. The process is simpler and cheaper than conventional processes using a solvent for a binder and the electrode has a mechanical elasticity approaching that of a sintered electrode and has a longer storage life since there is no residual solvent to reduce the active metal.
The high temp. battery includes a built-in heating agent using a mixt. of zirconium and ferrosilicon as a reducing agent, and metal chromate or a mixt. of metal chromate and potassium permanganate as an oxidising agent. The molten salt or solid electrolyte is non-conductive and inactive at room temp. and ion-conductive at high temp. The battery is used as an emergency power source for a rocket, ship or fire alarm. the weight of the battery is reduced and reliability of battery characteristics is increased by decreasing an amount of reaction product gas generated from the heating agent and increasing the safety factor.
Fuel cell is formed by assembling a repeated stack in the sequence (1) cathode; (2) a separator; (3) anode; (4) current collector, these components consisting of thin plates of the same size using an insulating frame round an active centre, the surfaces of the centres of (1,3) not facing (2) are fed respectively with oxidant and fuel, whereas both surfaces of (2) are fed with electrolyte. The frames consist of a circular ring contg. 12 openings with a pitch of 30 degrees, forming six pairs of channels in the stack for feeding oxidant to (1); feeding electrolyte to (2); feeding fuel to (3), removing used oxidant, removing electrolyte and removing reaction products. The fuel is pref. H2 hydrocarbons, alcohols, with O2 or air as oxidant. The cell has a circular filter press structure suitable for mass prodn.
Fuel cell is formed by assembling a repeated stack in the sequence (1) cathode; (2) a separator; (3) anode; (4) current collector, the components consisting of thin plates of the same size using an insulating frame round an active centre, the surfaces of the centres of (1,3) not facing (2) are fed respectively with oxidant and fuel whereas both surfaces of (2) are fed with electrolyte. The frames consist of a dodecagon ring formed by twelve segments each segment contg. an opening so that six pairs of channels are formed in the stack for feeding oxidant to (1); feeding electrolyte to (2), feeding fuel to (3); removing used oxidant; removing the electrolyte and removing reaction products. The fuel is pref. H2 hydrocarbons or alcohols with O2 or air as oxidant. Filter-press structure obtd. is suitable for mass prodn.
Fuel cell consists of a rigid stack formed by numerous bipolar electrodes sepd. by semi-permeable separators, each electrode comprising an insulating frame round an active centre and the separators using an insulating frame of the same size round a semi-permeable centre, one surface of each of the active electrode centres is fed with fuel and electrolyte, whereas the other surface is fed with oxidant gas. The upper and lower edges of the electrode frames contain numerous microchannels which are parallel and equidistant to each other, the upper channels supply the fuel and electrolyte whereas lower channels are used to remove the electrolyte and reaction products, and the sides of the electrode frames each possess a channel, one supplying and the other removing the oxidant gas. The filter press. structure is easy to make on an industrial scale e.g. the electrodes and their frames can be co-extruded as continuous strip.
Fuel cell formed by assembling a repeated stack of components in the sequence: (a) cathode, (b) separator, (c) anode, (d) current/collector, the components consist of thin plates of equal size, using active centres surrounded by an insulating frame, the surfaces of (a, C) not facing the separator are fed with the oxidant and the fuel respectively, whereas the two surfaces of the separator are fed with electrolyte. the frames have a hexagonal ring shape formed by two homothetic hexagons and each of the six segments possesses six pairs of channels for feeding oxidant to (a), feeding electrolyte, to (b); feeding fuel to (c), removing used oxidant, removing electrolyte, and removing reaction products. A fuel cell with a hexagonal filter press structure is thus obtd. which is easy to produce.
In a process for generating hydrogen, esp. for fuel elements, by reacting metals with aq. salt solns., the metal is first converted into pressed shapes and then removed mechanically as a powder from the shapes and introduced into the salt soln. The pressed shapes occupy less space in storage, are easier to handle and degas than powders and do not cause the blockage in feeding associated with powder.
In a fuel cell stack comprising a no. of fuel cells having phosphoric acid electrolyte, in which separator plates are provided between each pair of adjacent cells and at least one plate includes coolant passages parallel to the plane of the plate, cooler tubes are provided in the passageways with a gap between the outer surfaces of the tubes and adjacent surfaces of the passageways and the gap is filled with a heat transfer material consisting of phosphoric acid and a filler from SiC, C and graphite. The heat transfer material has a grease-like consistency, high thermal conductivity and is fully compatible with the fuel cell electrolyte.
In a fuel cell appts. including a no. of series-connected fuel cells comprising spaced apart electrodes each including a catalyst-electrolyte interface and using H-contg. gas fuel, unscrubbed air oxidant and alkali metal hydroxide electrolyte, in which detrimental CO3 ions formed in the electrolyte by reaction with CO2 in the air are removed by (a) providing a regenerator cell having spaced apart anode and cathode in series with the fuel cells, and responsive to the power demand of the load, (b) circulating electrolyte in a single pass (i) in parallel through the fuel cells then (ii) between regenerator cell electrodes, (c) contacting an unscrubbed air flow with the nonelectrolyte side of the regenerator cathode, (d) establishing and maintaining an OH- ion gradient between regenerator cell electrodes, the concn. at the anode being low enough for gaseous CO2 to be released from the electrolyte at a steady state rate equiv. to its absorption rate in the fuel cells as a function of the power demand of the load and (e) venting CO2 from the stack. CO3 ion level is economically maintained at a tolerable level, e.g. a regenerator cell removes CO3 ions formed in 60 fuel cells using &lt;1/60th voltage provided by fuel cell stack.
The level and concentration of the electrolyte in hydrogen/oxygen fuel cells is controlled by a tube, open at both ends, which dips into the electrolytic cell and receives the diluting water produced in the cell. An overflow in the tube at a certain distance H from the bottom end is dipped to a depth of L. The electrolyte level adjusts itself such that the ratio H/L equals the ratio of the electrolyte density to the overflowing reaction water density. This is a very sensitive arrangement which requires neither sensors nor power-consuming controllers or switches. It has no mechanically moving parts and is free from breakdowns.
A supported transition metal catalyst is prepd. by (a) contacting (i) a particulate polymer (I) contg. benzimidazo N gp. gps., derived from organic tetra-amine(s) and tetra-carboxylic acid or anhydride and having of surface area of 100-500 sq.m.pert g. with (ii) soln. of a salt of a transition metal, (b) recovering the particulate polymer in which the benzimidazo N gps. form a co-ordination complex with the salt and (c) reducing the transition metal cations of the complex to the metallic form. The supported catalyst contains 0.01-5, pref. 0.01-4 wt.% of the transition metal. The catalyst may be used at high temps. and/or in a caustic medium, particularly in a fuel cell in which oxygen and hydrogen react to produce an electric current and form water, in hydrogenation reactions of e.g. 2-20C linear or cyclic olefins. Olefin isomerisation and oxidation may also be carried out.
A carbonaceous material suitable for use in the electrocatalytic substrate of a fuel cell electrode is prepd. by (a) depositing a copolymer contg. at least 85 wt. % vinylidene chloride, balance one or more compatible vinyl monomers from soln. onto C particles having an average particle dia. of 0.07 u-130 angstroms and a pore size of 30-300 angstroms such that the copolymer contributes 1-15% of the total C content of the particle-copolymer mixt. and (b) heating to 700-1400 degrees C to pyrolyse the polymer and generate a porous C char. The electrode is useful in fuel cells having liq. electrolyte and gaseous reactants and operated at ambient temps. Polarisation voltage loss at the air electrode may be reduced for 30-50% at current densities of 50-800 mA/cm2 compared with polarisation of C black material of similar particle size and is only about 1/4 that of polyvinylidene chloride char alone.
Proton-permselective solid element (A) is obtd. by shaping 1 component consisting of heteropolyacids having formula Hm XxYyOz .nH2O (I) (where X is 1 component selected from B, Al, Ga, Si, Ge, Sn, P, As, Sb, Bi, Se, Te, I, and the 1st, 2nd and 3rd transition metals; Y is 1 1st, 2nd or 3rd transition metal component; m, x,y,z, and n each is a +ve no., and pref. m is 2-10, y is 1.-12, n is 3-100 when x = 1) and their salts. X and Y are not identical. Different transition metals can be used to replace X and Y in (I). (A) are used as electrolytes in fuel cells and as separators and membranes in electrochemical devices, e.g. in electric cells, such as fuel- and concn. cells, in systems for prepn. and purification of H2 under influence of electric fields and H2-detectors. They have excellent ion-conductivity from room temp. to 100 degrees C. Fig 1 shows specific resistance of a permselective element of H3 PMo12O40 .3OH2O as a function of temp. Resistivity is independent of frequency.
Ion-exchange group-contg. polymer (e.g. copolymer of tetrafluoroethylene with perfluoro-3,6-dioxa-4-methyl-7-octene-sulphonyl fluoride) is supported on a film-form supporting material having a number of voids consisting of linear moulding of melt-mouldable fluorine contg. polymer (e.g. ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-perfluorovinyl ether copolymer, etc) obtaining an ion-exchange membrane having a supporting material. The membrane can be used not only for electrodialysis, electrolysis, waste liq. treatment, desalting process, fuel cell, etc. but all under severe conditions such as oxidative condition or chlorine-generating condition; namely it can be effectively used as diaphragm in NaCl electrolysis.
The electrode has water repellant and water absorbing porous layers which are set on the metallic meshed sublayer. The water retaining layer is the catalyst which contains hydrophobic carbon mixed with active carbon and free of platinum or silver. The water repelling layer retains diffused gas, and is made from water repelling carbon with the hydrophobic material in proportion (50-50)%. Both layers have the same thickness.
A hydrogen fuel is supplied to a hydrogen fuel cell generator as follows. One metallic hydride is heated to produce hydrogen gas using the combustion heat of hydrogen gas produced by another metallic hydride. The hydrogen gas produced from the first metallic hydride is supplied to the generate electric power. Since the hydrogen gas is stored as the metallic hydride, the generator can be constructed without a hydrogen bomb.
Construction of the title cell is simplified (by dispensing the diaphragm) when the electrolyte contg. NaOH (I), NaBr (II) and NaI (III) has such composition that, at the cell working temp. one of the components remains solid, while the remaining components become molten. The working temp. of the cell is 210-350 degrees C and the electrolyte is prepd. by melting the components at 350 degrees C. The role of the diaphragm is played by the solid phase. The following comps. are given (in moles %): (1) (I) 7-50, (II) 1-10 and (III) 40-92; (2) (I) 5-50, (III) 1-10 and (II) 40-94; (3) (I) 5-50, (III) the rest and (4) (I) 5-60 and (II) the rest.
Electrochemical generator, esp. a fuel cell, comprises electrodes sepd. by a diaphragm defining cathode and anode compartments, the cathode compartment being supplied with hydrogen peroxide and an oxide bath resulting from the deconpsn. of a peroxide form of a cpd., esp. an anthraquinone deriv. such as the anthraquinone 2-7 disulphonate of an alkali metal (Na or Li). The low temp. performance of the electrode a the level at which oxygen or air is admitted as comburant in the fuel cell, is improved giving an improved yield of power.
The prodn. of Raney metal catalysts for electrochemical cells, esp. fuel cells, comprises producing a Raney alloy on the surface of metal whiskers and dissolving the inactive componente from this Raney alloy. Pref. a base metal acting as the inactive component of the Raney alloy is applied to the metal whiskers and the Raney alloy is produced by diffusion of the base metal into the whisket surface. Max. utilisation of the active material is ensured and the pores in the powder are kept large enough to alloy unhindered gas transport.
Cuprous ion-coordinated nitrile type polymers are obtd. by allowing polymers contg. nitrile radicals in molecule to stand in contact with cuprous cpds. (cuprous chloride, cuprous bromide, cuprous indide, etc.) in alkali metal halide solns. so as to coordinate-bond nitrile radicals to cuprous ions. Thermostable mouldings are obtd. by moulding granular or fine powder cuprous ion-coordinated nitrile polymers contg. 3 wt. % of copper with pressure. By treating the mouldings at &gt;700 degrees C, carbon mouldings are formed. Heat resisting paint films are formed by coating metals, etc. as the base material with the granular or fine powder polymers as they are or the polymers dispersed in solvents. Flame resisting and heat resisting fibres, catalyst electrode for fuel battery and selective permeable membrane are obtd.
In a battery of stacked fuel cells comprising (i) a series of cells electrically coupled in series, each cell having 2 spaced electrodes defining an electrolyte compartment and (ii) a means of sepn. delimiting 2 reactive-gas chambers on that side, of each electrode hot exposed to the electrolyte, &gt;1 reactive - gas is caused to pass in parallel through each cell in the battery but to enter into gaseous communication only with a part of one of the electrodes in each cell; the exhaust gases released from each cell are combined and the mixt. so produced passed in parallel through each cell, the gaseous communication this time taking place with a different part of the electrode; this process is repeated by combining the exhaust gases leaving the cells and causing the resultant mixed gases to pass in parallel through each cell, the gaseous communication in each case being with a different part of each electrode, until each cell has been completely exposed to the reactive gas. Process reduces the undesirable consequences of poor reactive gas distribution and non-uniform current distribution in cells coupled together electrically to form a fuel cell battery, and in addn. gives better consumption of reactive gas.
Design simplifications and increased reliability of fuel cell regeneration are ensured by lowering the current density of the electrodes to 30-35 mA/cm2 before discontinuing the reagent flow.    As soon as the gas pressures rise to 650-700 mm Hg the reagent flow is resumed and this process repeated periodically until all traces of gas have been eliminated.
Method of decarbonating a gas or mixture of gases is claimed in which the gas is circulated through 1 bed of LiOH in the solid state to fix CO2, the LiOH being used in a dehydrated state at 40-80 degrees C (60 degrees C). The gas and the LiOH bed are both preheated, the gas by means of a heater located in the gas input duct and the LiOH by means of a heater e.g. a hot fluid heat exchanger surrounding the LiOH powder. Used for feedng a fuel cell wth decarbonated air. The absorption of CO2 in LiOH is improved when it is powdered and heated to the temp range, esp. when dehydrated.
An energy conversion system, comprising (1) a hydrogen gas generator operating by an exothermic chemical reaction between a gaseous substance (Ie and a liquid substance (II), the latter being present in excess, (2) a conduit removing the gas produced, (3) a fuel cell receiving the gaseous product, and (4) a thermal engine which is powered by the heat from the exothermic reaction in the gas generator. Specifically, (1) is operated at 400-2400 degrees F, (I) is H2O and (II) is selected from Al, Na, Li, LiH, K, Ca, Mg and Si. The fuel cell is an H2/O2 fuel cell. In an alternative embindoment, after (2) the thermal energy is converted to useful energy in a thermal eugone and the H2 is converted into useful energy by reacting with an oxidant in an energy conversion device selected from an electrochemical reactor and a thermal eugone. A mobile, closed-system, chemically fuelled power plant is provided in which the thermal energy of the hydrogen-producing reaction is converted to a useful form of energy.
In a fule cell power plant, compressed air is fed to the cathodes of the fuel cells and is discharged, together with not spent fuel, into an autothermal reactor where a steam transformation, partial oxidation and CO conversion take place. The resulting reactor gases are directed th the fuel cell anode, to a gas burner which raises their enthalpy, and to a gas turbine to drive the air compressor. Water recovery section is obviated as the steam needed for the autothermal reactor is present in the cathode waste gases. The fuel cell power required for air compression is saved. The autothermal reactor needs no separate burner because the unburned hydrogen in the anode waste gases supplies the energy.
A fuel cell power station includes a compressor to supply compressed air to the oxidizing agent chamber in each cell. The compressor is driven by a turbine which receives steam from a circuit with a heat exchanger heated by the waste heat of the fuel cell. As the fuel cell power is not used for the compression of the oxidizing agent, the useful output of the fuel cells is increased. The water recovery section of the plant can be smaller, also the steam transformation reactors, if used.
In a fuel cell system, pressurized hydrogen is delivered to the anode gas space of the fuel cell from a reactor supplied with a pressurized hydrogen-containing fuel and heated by burning anode effluent gases, and compressed air at more than 2 atmospheres pressure is supplied to the cathode gas space of the fuel cell from a compressor driven by a turbine powered by pressurized cathode effluent gases to which additional energy has been supplied. System is more efficient and permits reduction in size of the water recovery condenser and of the steam reformer.
Fuel cell having an improved hydrogen ion conductive electrolyte which is used at low temps. of about 200 degrees C, comprises a hydrogen electrode, an oxygen electrode of oxygen ion-electron composite conductor, and a hydrogen ion conductive solid electrolyte consisting of sulphate of triethylene diamine (C6H12N2) or hexamethylenetetramine (C6H12N4). The fuel cell is used at low temps. of about 200 degrees C and has a low energy loss.
A cooling system in a fuel cell stack, having adjacent cells separated by conductive separator plates, comprises a plurality of cooler tubes having conductive walls disposed in passageways in the separators, and dielectric material disposed between the conductive plates and the conductive walls. Use of inexpensive coolants, having a low boiling point, being capable of transferring large amts. of heat at reduced flow rates through smaller tubes, and being non-inflammable, non-toxic, and non-deleterious to the cell in case of leakage is thus permitted.
In a fuel cell stack which uses an alkali metal hydroxide electrolyte which contains CO3-- ions due to contact with air (e.g. supplying O2) the electrolyte is distributed is parallel between the electrodes of the fuel cells and then to a regenerator cell. The CO3-- ions are converted to CO2 and OH- ions by providing na OH- ion gradient between the electrodes of the regenerator cell and the regenerated electrolyte is then returned to the cells. Single regenerator cell in series connection with fuel cell stack regenerate the electrolyte for the entire stack.
An oxidising agent and a reducing agent are circulated in a fuel together with an electrolyte. In the circulation system is provided a mechanism which ensures the oxidising agent in the electrolyte is mixed with the reducing agent in another electrolyte stream, these streams having been passed through the cell.
Fuel cell consists of an oxidizer chamber, cathode, a reaction chamber, a fuel chamber, and an anode. A gaseous oxidizing agent is used and a noncirculating electrolyte (30% KOH) is contained in the reaction chamber. The fuel is supplied directly to the fuel chamber. The cell withstands impact and vibrations, and is safe to operate.
A fuel cell with porous electrodes has an up-and-down moving electrolyte to let electrodes adsorb oxidiser (O, air) or fuel (H, CH4). Thus, porous C-fibre electrodes were impregnated with AgO (for the cathode) and Pt (for the anode) catalysts. The cathode and anode in a cell casing were sepd. by a spongy separator. From the bottom of the casing, a 30% KOH electrolyte was pumped in and out of the cell at given time intervals while O and H were supplied to the exposed electrodes from the top of the cell.
The heat and product mass e.g. water, in a fuel cell is controlled by drawing condensed water back into the fuel cell through capillary membrane, from a condensation zone above a vaporisation zone, excess vapour being removed via conduit and pressure relief valve and heat being removed by the condensed vapour passing back through membrane to again be vaporised.
Metal-gas cell e.g. a nickel-hydrogen cell, having a cell plates connected to a terminal (the distances between the cell plates and the terminal being different) wherein each of the connecting leads are arranged to have the same electrical resistance e.g. by having cross sectional areas varying directly with respect to their length. These leads are insulated and are preferably made of rectangular cross-section nickel and have equal thickness. Ensures equal current from all the cell plates i.e. improved efficiency and increased cell like.
In an electrical energy source comprising fluid manifolds and an electrolyte, one of the interfacing electrodes comprises a permeable metal layer with a number of separated metal fibre wicks secured to and extending from, the layer in parallel arrangement into the fluid manifolds. Each wick comprises a number of closely spaced metal fibres the parallel voids in which can be filled with electrolyte. The source is used in fuel cells and batteries e.g. fused carbonate fuel cells. Due to the high surface area of the metal fibre wicks the gas readily diffuses into the electrode surface and lowers the electrode overvoltage.
An electrolyte in an electrolyte compartment penetrated through a partition wall of a negative electrode into a compartment formed between negative and positive electrodes in an electrolyte container. A gas exhaust path at the compartment is connected to an electrolyte exhaust path.
In a gas or liq. fuel cell having an electrolyte tank or a liq. fuel tank, oxygen or air is exhausted through the electrolyte or liquid tank.
The fuel cell comprises a feed pipe for a gas exhausted through a gas diffusion electrode, a drain pipe for a gas exhausted from an electrolyte side, and a gas catalyzer introducing the two pipes.
A catalyzer is attached to a gas diffusion electrode side and an electrolyte side for a fuel cell using hydrated hydrazine or ammonia as a fuel.
Cleaning unit for exhaust gas is attached to the gas diffusion electrode side of a fuel cell using hydrated hydrazine or ammonia as a fuel, and a gas catalyzer is attached to the electrolyte side.
A heat exchanger and a by-pass having a concentration detector are arranged in an electrolyte circulation system for a fuel cell to detect the electrolyte concentration at a constant temperature.
A direct hydrocarbon oxidation fuel cell uses as the electrolyte CF3SO3H.H2O, a monohydrate of fluorine and carbon sulphonic acid, having a liquid state at the cell operating temp. The anode and cathode may be of noble metal, e.g. platinum, mixed with carbon and Teflon (RTM) and supported on graphite. Enables fuel cell operation with direct oxidation of hydrocarbon fuel, cell performance being substantially improved.
A high-temp. lithium/sulphur secondary battery contains in each cell of a stack a pressed disc of immobilised electrolyte between a pressed negative electrode disc of Li and a pressed positive electrode disc of a metal sulphide. An inter cell metal disc prevents chemical interaction and provides electrical contact between cells. Construction of the battery cell is simplified and eliminates use of costly insulating matls.
Hydrazine fuel cell contg. a hydrazine electrode and an air- or O2-electrode where, in operation, the electrolyte-hydrazine mixt. flows in a prescribed direction along the side (I) of the hydrazine electrode remote from the air- or O2-electrode. The novelty is that a membrane is located on side (I) and the diffusion-resistance of the membrane w.r.t. hydrazine decreases in the direction of flow of the electrolyte-hydrazine mixt. The membrane is pref. asbestos with thickness decreasing from 2.5-0.3mm in the direction of flow and with vol. porosity ca. 20%; alternatively the membrane may have a thickness of 1mm and the porosity increases in the direction of flow from 5-20%, and this membrane may contain ion-exchange matl. Prevents the self-decompsn. of the hydrazine.
Porous sheet is made by spraying a liquid dispersion of an org. polymer through an electric field so that the polymer is ppted. as fibres which are collected on an electrode. The fibres are removed from the electrode and consolidated into matting. Esp. for mfr. of porous diaphragms for use in electrolytic rolls, fuel cells, etc. The spinning conditions and field strengths may be adjusted to vary and control the coarseness of the ppted. fibres and hence the porosity of the product matting. All the fibres are collected by the electrode. Pref. for mfg. fibres 0.1-25 mu, pref. 1-5 mu in dia. made predominantly of a fluorocarbon polymer, esp. PTFE. The fibres are ppted. from a pressure spinning soln. of viscosity 0.1-150, pref. 1-10 poises contg. 0.2-6% wt. of a supplementary polymer chosen from polyoxythylene, PVA, polyacrylamide, or polyvinylpyrrolidone.
A component assembly for use in electrochemical cells comprises first and second components coextensive with a and adhered to opposite faces at 1 plastic, nonconductive network contg. openings, with active or inactive material within the openings contacting the faces of the two components. Pref. the first component is a metal node, esp. from Zn, Zn-clad steel, Al, Pb, Cd, Mg, Fe and the second component is a moulded cathode of oxidic material, esp. from MnO2, PbO2, Ni oxyhydroxide, mercuric oxide, Ag oxide and inorganic metal halides. An electrolyte, esp. aq. KOH contacts the faces of anode and cathode through the openings in the plastic network. Two components of a thin, flat cell are secured in spaced apart relationship, the adhesive bond being strong enough to avoid components separating due to swelling or gas build up during storage or operation.
A process is provided for burning (oxidizing) fuel by use of increase of reactivity of a system in virture of largely broadening the contact potential difference between electrodes in preference to catalytic ability of the electrodes. As raw material for an anode, large ionization tendency metals or alloys thereof are used such as I to V group metals. As an oxidizing agent and an electrolyte, materials difficult to directly react with the anodic material are selected. Fuel is dissolved in alcohol and activated by saponification or emulsification to ionize the fuel with ease.
A regenerative hydrogen-oxygen fuel cell system has a fuel cell assembly and an electrolysis cell assembly, each having a hydrogen electrode, a matrix assembly and an oxygen electrode the oxygen electrodes of the two assemblies being of different materials and the hydrogen electrodes facing each other, a water matrix being disposed between and in contact with the hydrogen electrodes for transporting water between the cells, and a water storage matrix associated with the oxygen electrode of the fuel cell for storing water produced during fuel cell operation. Can be completely sealed, yet capable of 100% discharge and full recharge. Provides efficient gas and water transport without moving parts, and has improved performance and longer life.
A high temp. battery comprises a solid state electrolyte (I) having oxygen ion conduction at a high temp; a positive electrode (II) having oxygen ion conduction and electron conduction at a high temp; and a negative electrode (III) being active to fuel materials at a high temp. (II) comprises bismuth oxide, sodium- or ion-oxide, perovskite-structure oxide doped with oxide of alkaline earth metal, r zirconium oxide doped with thorium oxide (I) comprises zirconium oxide contg. 15 mol.% calcium oxide, 9 mol.% yttrium oxide, or 9 mol.% ytterbium oxide. (III) comprises tungsten carbide, or sodium-tungsten bronze.
A fabric reinforced elastomeric container is made by applying a fluorocarbon elastomer inner layer to a former, applying a solvent solution of a fluorocarbon elastomer over the inner layer, pressing at least one layer of fabric onto the liquid layer to cause the liquid to strike through the fabric, applying at least one further coat of fluorocarbon elastomer over the fabric, curing the assembly thus formed and finally removing the former. Formers are preferably of plaster of Paris and are removable by soaking with water. All layers may be applied by spraying, dipping, brushing or the like. A bubble-free, leak-free container is suitable for use as a high temperature resistant fuel container.
During the operation of H2NNH2 fuel cells, the H generated in the cell is reacted with O in the presence of an appropriate catalyst and the heat of reaction is used for heating of the electrolyte. The H2O produced in the fuel cells is evapd. by heating, and hence the electrolyte vol. can be maintained const., and also the electrolyte concn. can be kept at optimal values.
In a filling system for electric cells consisting of a space for a liquid electrode, an electrolyte and a wire mesh wick for the liquid electrode to wet the electrolyte surface, liquid electrode material (Na or Li) is then introduced in the cell space and the wick is brought into contact with it. Finally a pressure is applied which is adequate to force the liquid electrode material through the wick until it wets the electrolyte. This reduces the time required for the electrolyte surface to be wetted which would take several hours at 360 degrees C operating temp. The delay in reaching maximum output is greatly diminished.
Al fuel cell comprises a cell reaction chamber having a cathode and an anode collector, an electrolyte passageway communicating with the cell reaction chamber, and powdered Al anode active material injected into the electrolyte passageway, and coated with PVA or polyvinyl butyral which is chemically and soluble in the electrolyte. Al hydroxide is used as the electrolyte.
Liquid fuel cell comprises a composite electrode fabricated by uniting a porous oxidising electrode, a separator and a porous fuel electrode as one body, the composite electrode fixed to a peripheral portion of a cell vessel in a liquid-tight manner, an outer surface of an oxidising electrode side of the composite electrode being in contact with an oxidising agent e.g. air, an outer surface of the fuel electrode side being in contact with liquid contg. an active fuel and an electrolyte, and only the liquid penetrating the fuel electrode reaching between both electrodes.
A liquid fuel cell comprises an air/oxidation electrode; a fuel electrode having one surface coated with a porous film comprising insulating powder and electrolyte-proof resin; and an electrolyte; the other surface of the fuel electrode contacting the electrolyte, which contains dissolved fuel.
In a battery having self-discharge characteristics, a high resistance element is connected across anode and cathode to provide a predetermined low currend drain on the battery. In an embodiment, an article operable by 1 batteries has a high resistance element mounted in the battery compartment to connect across the battery terminals and provide the low current drain. The low current drain on batteries subject to self-discharge increases the shelf life of the battery. Retained capacity was increased under various storage conditions, including 20 days at 75 degrees C., when 4 out of 6 unloaded batteries had no usable capacity but all batteries on 10,000 omega load retained 77% initial capacity.
Gas absorption capacity of the title material is increased twofold and its activation potential reduced by 2-4 times when the Ti powder is rolled into a strip, heated to 750-830 degrees C for 3-5 hrs. in argon atm., cooled, heated again to 900-940 degrees C for 3-5 hrs. in argon atm. and finally annealed by heating to 800-850 degrees C/4. 10-2 mm. Hg for 2-4 hrs.
An elastomer based on a peroxide-crosslinked EP- or EPDM rubber blended with a polyolefin is used in mfr. of a sealing frame body(gaskets) in electrolytic cells contg. strong acid, esp. in fuel cells. The matl. combines stability to strong acids with thermal stability.