Sheets formed from carbonised polyacrylonitrile fibre and PTFE fibre in a 7:3 ratio are laminated with PTFE sheets and fused together at 350 degrees C to form a porous sheet. One side is sprayed with an aq. suspension of PTFE contg. activated C with a Ag catalyst content and the product compressed after mounting on a Ni mesh, then finally heated to 380 degrees C for 8 mins. A rigid electrode is produced.
A fuel electrode for a fuel cell using a liq. fuel comprises a porous, catalyst-bearing hydrophobic sheet nonadhesively secured to a conductive base so as to form a passageway between the two, small enough to permit movement of fuel by capillary action. The fuel passes along the passageway and through the porous sheet to contact the catalyst and the electrolyte. The hydrophobic sheet may be inorg. fibrous material or an org. polymer, esp. polymeric acrylic fibre paper or PVC or polyethylene.
A battery electrode, partic. a Zn electrode, is made by mixing together an aq. mixt. of 75-99.5%, pref. 85-97 wt.% electrode materials, pref. Zn oxide particles of 0.1-10 mu size, and 0.5-25%, pref. 3-15 wt.% water dispersible latex type alkali-stable polymer, pref. PTFE having particle size of 0.01-10 mu, casting a film of this mixt., drying it at 60-100 degrees C for 2-24 hrs., sintering the dried film at 230-375 degrees C for 2 mins. - 2 hrs., rolling the sintered film at 200-300 degrees C for 10 mins. - 2 hrs., to bind the electrode particles together, grinding this film to a fine mesh particle size and then compacting it to form the electrode, which is highly reactive, is stable retaining its capacity over long periods of charge-discharge cycling and is of porous structure.
The battery comprises a cathode activator of silver oxide or nickel oxide, an anode activator of zinc and an electrolyte, zinc oxide or hydroxide. The anode has high discharge capacity more than discharge capacity of the cathode, and the cathode and the anode are fully charged when the battery is charged initially. Deterioration of the anode activator activity is reduced.
The decrease of capacity due to the formation of dendrite zinc during charge and passive state during discharge is prevented by using a zinc negative electrode contg. tellurium cpd.
The capacity stability of the battery is improved by addn. of Te cpds. to the alkali electrolyte. Typically 0.4g, TeO2 is used with 11 7N KOH.
The cathode is prepd. by adding to the styrene-group ion-exchange resin 0.1% of divinyl benzene and heating this mxiture at 100 degrees C for 5 hours. The dried resin thus obtained, together with 0.1% of barium sulphate, is mixed with a paste of active material to prepare the cathode.
Gas depolarised battery of one or more cells is enclosed in a box designed to control the input of depolarising gas to the region surrounding the anode in sufficient amount such that the cell (battery) is time limited in its ability to maintain a flow of current same as that possible without the box. This is effected by having a number of holes pierced in an outer shell surrounding the box, some of which may be closed off at will to restrain the polarising gas. Specifically the depolarising gas in air.
In an example acrylonitrile fibres are heated at 2000 degrees C to form carbon fibres. The carbon fibres are short fibres of PTFE, are mixed to make a thin film sheet of non-woven cloth (10% carbon fibre component) having a thickness of 0.2 mm. One surface of the thin film sheet is coated with a 10% pyridine soln. of silver acetate. The coated sheet is heat-treated at 300 degrees C to decompose Ag into Ag. Thereafter, a Ni net of 80 mesh is placed on the Ag-deposited surface of the thin film sheet. The Ni net-placed sheet is pressed at a pressure of 1 ton/cm2 to make an electrode which acts effectively as an oxygen electrode.
The electrode has as its base structure a porous polyethylene fluoride sheet formed so that the sheet portions at both ends can be bound together and are integral with the porous part of the sheet. The bindable sheet portions can be bound simply and securely, and the electrolyte prevented from leaking so that electrode performance is improved.
The gas electrode has an electrolyte-proof support, a catalyst retained by the support, and a pulverized or fibrous water-repellent substance attached to the supporter on the side where it contacts the gas. As support is used a sheet of non-woven cloth or cloth consisting of any fibre of polyamide, polyester, polyethylene fluoride, polyvinyl chloride or polyvinyl alcohol. The catalyst is selected from precious metals belonging to Group 8 of the Periodical Table such as Pt and Pd, and other metallic substances like Ag, Cu etc. or their alloys or a mixture of more than two of them, activated carbon or carbon material with any of the above catalytic metals deposited on it, all of them being able to adsorb gas when contacted with it. As water-repellent substance polyethylene fluoride, polystyrene, polypropylene, and polyethylene, are used.
The electrode is composed of a double-layer, one layer of which is on the side of electrolyte and the other on the side of gas; the layer on the side of electrolyte being formed by applying pressure to a mixture of powdered fluorine resin and powdered platinum black and by heat treating the mixture at a temp. at which the resin melts, and the layer on the side of gas being pressure formed without heat treating a mixture of powdered fluorine resin and powdered platinum black. The electrodes enable fuel cells to operate at high current densities and for longer periods than those contg. conventional electrodes.
A method of making battery plate gratings consists of laying longitudinal and transverse strips of plastics, pref. PVC, onto a long band of fibrous fabric as it moves longitudinally. As the band is conveyed longitudinally on a moving support it passes beneath a number of laterally spaced feed heads which apply molten plastic onto the fabric, this producing longitudinal, parallel ribs; the fabric band also passes beneath a device applying successive transverse strips of the plastic, so that when the plastic has set a grillage is formed. Alternatively, the same system may be used but pulverulent instead of liquid plastic is applied.
A single cell or a battery of cells is closed by a single piece plastic moulding esp of 'styropor' (RTM) which is a friction fit over the edges of the outer and dividing walls using grooves moulded in it, the breather hole forming an annular shoulder in the bottom of the moulding seating on the depolariser bag. Reduced labour and mfg. costs compared with e.g. pitch seals over the air chamber which require separate operation for insertion or forming of a breather vent.
The ion transport medium comprises an inert porous matter of mineral fibres and fluorocarbon resin-bonded composites of mineral particles to contain and retain the non-aq. electrolyte. The particles and fibres are chemically inert and electrically non-conducting and the electrolyte comprises a mixture of an ionic salt contg. the ion to be transported and an inorganic solvent.
A dry electric cell assembly, consists of a cell fitted in a tubular insulating sleeve surrounded by a metal casing. The sleeve is closed at one end by a plug of insulating material. Pref. the plug fits into the open end of a zinc cap electrode and has an inner sleeve part which seals resiliently round a carbon rod electrode. Metal end closures which engage the cap bottom and the rod end, are jointed to the ends of the casing by rolled over flange joints so insulating material of the sleeve at one end and of the plug at the other end, is interposed between the closure and casing. A shoulder on the plug engages coterminous ends of the cap and sleeve. The sleeve has an internal sealing flange between the cap bottom and closure. Leakage and drying out are prevented without pitch sealant. The sleeve and plug are pref. of low density polyethylene.
Separator is composed of an elastomer together with suff. C black to render the mixture electrically conducting, laminated onto metal or graphite. Separator is chemically inert while possessing suff. conductivity to give the cell a low resistance. Elastomers are prefd. because they confer elasticity on the system with a high proportion of C black. The mixture should have a resistivity of is not &gt;0.254 ohm-cm2/cm. Prefd. elastomers are natural rubbers, synthetic rubbers based on olefins copolymers of butadiene/styrene, isobutylene and conjugated dienes, nitrile rubbers or 'Thiokol' (T.M) butyl rubbers absorb most C black, pref. used in a proportion of 75-175 pts/100 pts. rubber. The substrate may be of brass, steel, Cu, Nb, Mo, Ta, Zr or Ni alloys, partic. 'Hastelloy' (T.M), or of graphite. The laminate is moulded under heat and pressure.
A method of joining together two plastic objects to form a fluid-tight seal between them which can be released later when desired, esp. for bonding a lid onto an accumulator, uses thermoplastic adhesive. The adhesive is applied to the mating surface of one object, then the other object is placed on, and both articles, together with the adhesive layer, and heated sufficiently to melt the adhesive, thus bonding the objects together, a prefd. adhesive is a combination of ethylene vinyl acetate copolymers and a glycerine ester of a hydrated wood resin. The battery components are pref. pollypropylene.
Storage plate has an electrode coated with CdS, in which positions of different conductivity can be produced using light or an electron beam and maintained by applying an electric field perpendicular to the CdS coat. The plate comprises an electrically insulating substrate with a coating of a conducting material, which does not react with CdS, as lower electrode, then a 2-15 mu m thick thermally treated CdS coating, then, over (part of) this, a composite film of 2 materials of differing conductivity and finally a metal film forming the upper electrode. The composite film consists of a metal, pref. Al, Ag, Pt, Sn or Au, or semi-conductor material, pref. Ge, and a dielectric material, pref. SiO or MgO, a Au/SiO film being esp. suitable.
Graphite electrodes esp. for light-wt. galvanic cells, esp. for cold-combustion of energy-supplying chemical systems are produced by compressing thermoplastic foils, esp. &gt;300 mu thick, coated on one or both sides with layers of powdery or flaky graphite, esp. 1-500 mu powdery graphite, at elevated temp. Pref. thermoplastic foils consist of polyolefines, and PVC and polyamides may also be used. Pref. coated electrodes are mechanically treated, e.g. brushed or buffed, and subjected to a second compression whereby graphite grains of dia. thickness of plastic foil are pressed through coated plastic foil.
Method comprises preparing a W/O emulsion from a polymer soln. in a water-immiscible solvent having b.pt. &lt;100 degrees C, applying the resulting emulsion to a base material, then drying it. The resulting sheet has fine cells and therefore excellent gas-and moisture-permeability, and is used for synthetic leather, battery separators, etc.    Suitable polymers include benzene-soluble styrene-butadiene copolymer, polybutadiene, nitrile rubber, polychloroprene, butyl rubber, acrylic rubber; benzene-and chroroform-soluble polystyrene; benzene-soluble polyvinyl acetate, etc. When producing synthetic leather, flexible polymers such as polyurethane elastomer, polyester-polyether block copolymer etc.a re prefd.
Packing comprises polyolefine synthetic resin having melt index 0.2-1, stress crack resistance and easy mouldability ensuring avoidance of electrolyte leakage.
Flexible porous battery separator comprising a flexible envelope in which flexible porous sheets e.g. chrysotile asbestos are treated along their edge portions with a sealant consisting of a mixt. of neoprene and either polysulphone (PS) or polyphenylene oxide (PPO) and heat sealed. This heat-sealed flexible envelope is then treated with a film comprising an inorg. separator material and an org. binder. The film conts. mainly inorg. material together with small quantities of K titanate fibres and cured org. binder. A battery is formed by inserting an electrode into this flexible separator and contacting it with an electrode of opposite polarity. This battery separator has low electrical resistivity, better resistance to alkali at high temps. better bond strength and batteries made using this separator have extended life due to reduced electrode (e.g. Zn) penetration into sealed edge portions.
Strong, flexible inorganic fibres for mfr. into battery electrodes comprises particles of inorganic material bonded into a fibre with 10-50 wt % total solids plastic binder. The fibres may be sintered to remove organic material. The inorganic material is from zinc oxide and zirconia, (pref) of alumina, beryllium oxide, titanates, aluminosilicates, ZrO2, SiO2 and solids solns. of zinc oxide with Zr, Sn, Ti, Cr, V, Co, Fe, Al, Ga, Y, Sc, Ni, Mn, La, Ce, Ba, Mg, Cu, Ag, and Li. Pref. binder is polyphenylene oxide, and a plasticiser, esp. polypropylene polyazelate may be included.
Battery plates of plastic material, coated with a metallic film are electrically bonded without damage to the plastic by clamping the plates of a compartment in a packet, and holding them upside down with the terminal projections of the metallic films within the area of connecting link moulds arranged in a suitable fixture. A lead alloy is then poured into the moulds and is allowed to cool before the packet of plates is removed and loaded into the battery box, where the connecting links are fused together normally.
Making fuel cell electrodes of the type having a porous conductive catalytically active layer contg. a hydrophobicising agent which is soluble, by mixing the active powder with a soln. of the hydrophobicising agent, adding a pptg. agent to deposit the hydrophobicising agent on the particles, filtering, drying, grinding the particles, then moulding, compressing and heating them. Simple method for controlling at size of the hydrophobicising agent particles.
The cathode is of a network structure in which a 0.22 mm. dia. Ni wire in the form of a 20 gauge mesh is coated with a paste of CaO and Ni powder in a wt. ratio of 10:1, using a 1% ethylene glycol soln. in polyvinyl alcohol as a binder. After drying 3 such meshes together with 2 nylon meshes are formed into a laminate and compressed to approx. 40% of the orig. thickness.
Battery separators that are thin, flexible and have a low electrical resistance are obtd. by dissolution of vinyl chloride-vinyl acetate copolymer in an org. solvent; dispersion of an inorg. filler in the soln; adjustment of the soln. viscosity to 30-400 CP, and then the coating on an unwoven cloth, consisting of vinyl-gp. macro-molecular fibre, with the viscous soln. followed by drying the coating. Battery separators have improved flexibility and electrical resistance and permit accumulators to be mfd. in smaller size.
The separator is formed by jetting from the nozzle very fine powder of polypropylene, polyethylene or synthetic resin resulting from acrylonitrile-styrene copolymsn. making the superficial particles of the powder fuse together by heating as the powder is sucked by a machine designed for the purpose, and then pouring the treated powder into the mould for the separator.    The separator, except for part of its superficial particles fused together, when cooled, constitutes a conglomerate of synthetic resin particles having voids between the particles making it permeable to the electrolyte. The separator, after being formed, has a solvent sprayed upon its surface to give it rigidity.
Heating elements are mounted inside the battery, acting as (part) supports for the electrodes but are electrically insulated from them. The heating elements may be surface coated with conducting layers carrying the heating current, which are insulated and carry a metallic coating to convey the current to the electrodes.    The electrode plates may consist of polypropylene, polyethylene or PVC fabric tubes filled with PbO2 having a central wire to conduct away the current generated.
Electrode for rechargeable cells comprises an active material (pref. Zn) in the form of a grid or gauze, sandwiched between two plastic layers at least one of which is an ionic conductor e.g. PVA. The other layer may also be PVA or may be a material permeable to gas esp. H2, e.g. PTFE. The electrode is made by pressing the Zn between the two plastic films in a mould with flexible faces, at 210 degrees C and 10 kg/cm2 if both films are PVA, or at 240 degrees C, 10 kg/cm2 for one PVA, one PTFE.
Metal-coated glass or ceramic fibres for use as electrically conductive composite material, e.g. battery electrodes, are mfd. by placing the metal-coated fibres together and effecting adhesion between the fibres by welding the metal, pref. by heat and/or pressure. The metal may be Pb or a Pb alloy with a lower softening point than that of the glass fibres, and these can be placed on a carrier of heat-hardenable or thermoplastic material e.g. phenol formaldehyde, polyesters, polyurethane and epoxy resins; polyolefines, e.g. polyethylene or polypropylene, polyamide, polyesters, e.g. polyethylene terephthalate or PVC.
Each cell of a metal/air battery has two insulated air electrodes, one on each side of a metal electrode. Each air electrode carries a catalyst in a layer of porous material. Each pair of layers is welded at the periphery to form a cell, with a removable pin protruding from the periphery. The pins locate the cell in a mould which is filled with a thermoset. The pins are finally removed to allow the electrolyte access to teh cell.
A separator for an alkaline primary cell consists of a semi-permeable membrane, an alkali-resistant synthetic fibre layer for reinforcing the membrane and a layer of pulp made from natural fibres for absorbing the electrolyte, all the layers being bonded together by a paste. Pref., the semi-permeable membrane is cellophane foil or parchment paper, the synthetic fibres are retained in a nylon or vinylon fabric, the pulp layer is absorbent cotton and the paste is methyl cellulose or sodium CMC.
Glass mat contg. resin for storage batteries is prepd by immersing or spraying a mat of glass fibre in or with a resin soln, then dried to harden the resin. The resin soln is obtd. from a copolymer of 7-30 wt.% acrylic (1-4C) alkylester, e.g. ethyl-, iso- or n-butyl acrylate 55 wt.% alpha, beta- monoethylenically unsatd. carboxylic acid, e.g. (meth)acrylic acid, and remainder being a monomer e.g. styrene, methacrylic ester, acrylonitrile, etc. by neutralising with an alkali soln at &lt;100 degrees C. The resin compsn should have pencil hardness &gt;2H.
The alkali cell comprises a cell casing of Re or Ni, a cathode body mainly consisting of Mn O2 and graphite a cylindrical separator, an anode collector of Fe, a resin sealing member, a positive and negative terminals, a resin tube and an outer casing. The anode is made by mixing an amalgamated zinc powder with a binding agent which is dissolved in alkli soln. and then moulding the mixt by heating.    The anode body placed in the separator, is gelled by addn of an electrolyte. Since the zinc powder is uniformly dispersed in the electrolyte, effective surface area of zinc powder can be increased and cell performance is improved.
Electrolytic cell having at least one separator, between the anode and cathode, which consists of a polymer soln. which has been directly deposited on a first electrode, forming a solid "skin" aftery drying and which is swellable in contact with the electrolyte; and a second electrode directly applied onto the surface of the separator coating in form of a suspension of granular active material in the electrolyte.
The cathode of the liquid ammonia battery consists of an active material of org. nitro cpd., conductive agent powder, bonding agent and mercury sulphate anhydride &lt;15 wt.% per mixture of the active material, the conductive agent is KSCN, NH4SCN and graphite. The bonding agent is polyethylene, polystyrene and polyvinyl chloride. The organic nitrocompound is selected from nitrobenzene, metadinitrobenzene, 2.4.6-trinitroanaline, 2.4-dinitroanaline, 2.4-dinitrotoluene. The anode is conventionally Mg, zn or Pb.
The sheet may be prepd. by sintering, moulding a powdery thermplastic resin to produce a porous plate at between the second transition point of the resin and its melting point. The prod. has a thickness of 0.1 mm and a porosity of 13-30%. The resin may be polyethylene, polypropylene, polymethylpentane, polyvinyl fluoride, polyvinylidene fluoride, polyvinylchloride, polyvinylidene chloride, polyamide, polystyrene, polymethylmethacrylate, polycarbonate and aromatic polyester.
Cell comprises 1 anode 1 associated cathode and electrolyte at least between the anode and cathode all enclosed within a case or held assembled by a structure, the case or structure being formed such as to allow ingress of a depolarising gas to the cathode at such a rate that the cell or cells is/are limited to be capable of maintaining a lower current drain than would be possible if the case or structure was not provided.
Process comprises adhering a synthetic resin soln. comprising co-condensation resin of dichlorodiphenyl-sulphone with bisphenol and cyclohexanone resin solvent, to a plate-like or porous substance and then contacting resulting material (by impregnation, spraying or non-solvent atmosphere contact) with a non-solvent of the synthetic resin (ethanol, isopropylalcohol, n-butylalcohol, n-propylalcohol etc.), followed by drying. Simultaneous contact and drying, or acceleration of solvent/non solvent substitution is effected by a higher non-solvent temp. Uses of material include battery separators, electrolysis membranes, diffusion dialysis membranes and permeable sheet.
A device for automatically topping up the cells of an electric battery comprises bored stoppers projecting into their respective cells, connected to a common water supply conduit and acted on from below by an elastic portion of a float. Specif. the whole float may be made of elastic material or may comprise an expanded polystyrene body with an elastic, e.g. silica rubber, disc insert. The flow of water from a reservoir may be controlled by a solenoid valve.
Electroconductive, micropore-free powder (pref. carbon black) is dispersed in water, mixed with an aq. dispersion or a soln. in an organic solvent of a hydrophobic agent (PTFE, polyethylene, polyisobutylene, polypropylene, natural or synthetic rubber), opt. at an elevated temp. the mixture is homogenised; the dispersion medium is removed; and the solid product is dried and ground. Opt. the stabiliser (capillary-active material) and the product is ground again. A uniform deposition of the hydrophobic agent is attained.
The positive electrode is mfrd. by presence forming a mixt. of nickel nitrite ammine and nickel hydroxide-the latter may be dispensed with in some cases - with an electroconductive material and synthetic resin binding agent, and the subjecting the product to electrolysis. The use of nickel nitrite ammine as active material enables the cathode porosity to be high even if the forming pressure is high and thus serves for making the electrode mechanically stronger and more utilizable. By mixing nickel hydroxide with the active material at appropriate ratios, the porosity may be adjusted.
The gas diffusion electrode comprises an iron porous sintered body, one surface of which is coated with a C-contg. layer consisting of a mixture of C powder and a fluorine resni powdery binder, the uncovered surface of the iron sintered electrode contacting the electrolyte.
Secondary air cell comprises a negative electrode which contains metal active materials which are consumed by discharge, an air electrode which contains a reducing catalyser for activating oxygen, and electrolyte. The air electrode is prepd. by spreading a paint comprising CoAl2O4 powders, LaCoO4 powders, and hydrophobic binders of PTFE and polytrifluoroethylene onto a porous base of 35% porosity, consisting of PTFE or polytrifluoroethylene to form a catalyser layer, a porous collector of metal net which has been previously plated with nickel is put on the catalyser layer, and they are heated.
The magnesium dry element battery comprises laminated magnesium dry battery elements, a vessel and a sponge board having bubbles opened to the outside of the dry battery. Removal of H2 prevents Mg(OH)2 formation.
The heat-shrinking tube prevents leadage of electrolyte from the battery and electrically insulates the dry element battery from an outer metal sheath. The dry element cell comprises a dry cell element, a tube of heat-shrinking synthetic resin covering the element and an outer metal sheath, the heat-shrinking tube having contraction 4 to 15% in the direction of radius of the tube. The heat-shrinking resin is selected from polyvinyl chloride, polyvinylidene chloride and polypropylene.
The 20-1000 mu thick films are oriented in 2 direction, pref. at right angles to each other, either consecutively or simultaneously by 1.5-5 times in each direction at -10 to 200 degrees C, pref. 19-30 degrees C, in air or liquids which do not dissolve the PTFE and which have a surface tension low enough to allow them to penetrate into the pores formed during orientation.    Process yields films with fine, open cells, high strength, good pliability and high gas permeability. The films can be used for diaphragms in electrolysis, fuel cells, alkali cells and for the separation of isotopes, esp. for corrosive gases e.g. UF6 or BF3.    The permeability is almost independent of the gas pressure.
Title cpd. is used as cycloaliphatic amine in a hardener for epoxide resins. It is esp. suitable with resins used for casting battery blocks, partic. fuel elements, when it is used in the form of an adduct with an epoxide resin. The cured resin has max. oxidn. resistance, is dimensionally stable but not brittle, can be machined well and has a hard, glossy surface. Cured resin has good transparency and is only slightly yellowish. Cure takes place even at room temp.
Air-permeable films which are impermeable to electrolyte, for "self-breathing" gas diffusion electrodes in electrochemical cells, esp. fuel cells or metal/air cells, consist of 2 firmly-bonded layers of F-contg. polymer, the first a mechanically stable, sintered layer and the second an unsintered microporous layer. These films are light, thin and have adequate mechanical stability and also are (partly) microporous, hence ensure better pressure compatibility, i.e. greater resistance to passage of electrolyte without reducing O2 diffusion.
Process comprises causing a synthetic resin film thermally fusible for binding to form upon at least one of the places where plates are connected with separator ribs, and then compressing the film while applying heat in order to combine it with the parts of the battery's elements. The synthetic resin of which the film chiefly consists is synthetic rubber of polyisobutylene gp., etc. This resin, with some wax, etc. is mixed uniformly and is dissolved in a solvent. The resultant soln. is coated on the separators or plates at the portion requiring the coating, and then the solvent is evaporated to have only the resin film formed on those parts of the element.
The hydrophobic base material, e.g. felted polypropylene, nylon or Teflon (RTM) is immersed in a soln. comprising 15 g. KMnO4, 6 ml. 96% H2SO4 and 200 ml. H2O, and the soln. is heated to 20-95 degrees C for 5-30 mins. to coat the material with black hydrophilic MnO2. The coating is very inert chemically and is long-lasting. The separator is suitable for use in batteries and fuel cells.
Battery comprises a discharge cathode of active C or porous N contg. active catalytic metal, an anode of porous Cd an alkaline electrolyte, and a discharging cathode consisting of Ni, Fe, Cr, Co, or their alloys.
Polyacrylamide is adsorbed on a separator body of fabric or non-fabric mainly consisting of synthetic resin fibre. The polyacrylamide adsorbed on the separator body is stable to an alkaline electrolyte such as a concn. KOH and improves the permeability of electrolyte and electrolyte keeping ability.
An electrolytic cell diaphragm consists of a preformed asbestos matrix impregnated with a polymer. The diaphragm is made by impregnating the matrix with liquid polymer, heating the impregnated matrix between 25 degrees C and 400 degrees C drying it between 25 degrees C and 120 degrees C,sintering the polymeric material between 40 degrees C and 400 degrees C finally laminating the thus formed softened diaphragm to a porous metal or plastics substrate at polymer sintering temp. and 10 to 1500 p.s.i.g. Diaphragm has improved strength and gives easily reproducible permeabilities merely be altering the amount of polymer. The polymer may be PVC, polybutadiene, polychloroprene, polyisoprene, polyethylene, polybutylene, polypropylene, polyurethane, polychlorotrifluorethylene or PTFE.
Synthetic resin is introduced e.g. injected into a mould defining the outer walls and the compartment walls of the casing. After moulding the walls a portion of the mould is moved so that the mould also defines the base of the casing, further resin is introduced into the mould to mould the base integral with the casing walls.
Fuel cell electrode for use in acid media and comprising a W catalyst prepd. by the redn. of tungsten oxides in H2/CH4 (pref. 10% CH4) for 1-4 hrs. at 750-900 degrees C., with rapid heating and cooling (20 mins.). The W is mixed with 5-35% polytrifluoroethylene or polytetrafluoroethylene and 30% C and pressed at 40 kg/cm2, 280 degrees C, for 15 mins., cooled with pressure applied.
The porous plate, pref. of Ni with 35-80% porosity, and its porous projections, allows the electrolyte to circulate and still maintain constant contact with the anode. The purpose is to provide a constant amount of electrolyte in contact with the electrode to ensure a constant electrical output, and also give a built-in cooling effect on the electrolyte. Electrodes pref. comprise light webs which lie in a catalyst compsn. contg. a hydrophobic polymeric binder, pref. PTFE.
Inexpensive, erosion-free, gas-porous anode for use with e.g. alkali/Cl2 cell, comprises (a) gas-porous conductive base metal having anodic polarisation comparable to Ti (b) a non-conductive surface on the gas-impermeable parts of the side facing the cathode, and (c) a coating of anodic material on the gas-impermeable portions of the opposite side. Pref. base metal is Ti or Ti alloy.
Method of making an electrode esp. for an alkali cell, comprises providing an electrode material powder layer having a great number of metal fibres arranged and embedded in the direction of thickness of the layer and an electrically conductive substrate embedded perpendicular to the metal fibres. The powder layer contains a binding agent and pressure is applied to the electrode material powder layer in the direction of its thickness to deform the metal fibres irregularly.
The cathode body is a pocket type electrode comprising a cathode mixture inserted into a porous cylindrical pocket of nickel, the mixture consisting of nickel hydroxide powder and graphic powder.    The anode body surrounding the cathode is a paste type electrode comprising a core member of a nickel net coated with anode paste consisting of cadmium (hydr)oxide, powder of conductive material such as iron, nickel or graphite and a binder of carboxylmethylcellulose. The anode body is formed in such a manner that its end portion may extend outwards in the tangential direction of the circumference. The end portions of the anode body are in good contact with an inner surface of the outer container which serves as either positive or negative electrode.
The sealing film is of carboxymethyl cellulose or polyvinyl alcohol and prevents ingress of air into the cell to corrode the Mg electrode during storage. Cell is rapidly commissioned on immersion in water.
The Mg electrode is formed from several Mg(alloy) plates bonded by a electroconductive binder or arc welding. The two electrodes are sepd by a microporous synthetic resin, or vegetable fibre sheet. Short-circuiting due to peeling of electrodes is minimised.
A metal plate is coated on both sides with a resin gasket, that on the underside being 2-3 times as thick as that on the upper surface. The plate rests on protruding shoulders of the battery casing, and the upper part of the case is bent over and clamped onto the seal to compress the gasket to 40-60% original thickness. Leakproof character of the batteries is improved.
A dense graphite structure comprises, by wt., 5-25% of a thermosetting phenolic resin binder, and 75-95% graphite powder having max. particle size is not &gt;20 mu m and the following size-distribution: 80-160 mu m - 37-76%; 60-100 mu m - 20-74%; 50-80 mu m - 10-48%; 40-60 mu m - 3-23%; below 50 mu m - 1-12%. The binder is mixed with a liq. dispersant, and the graphite particles are admixed therewith. The mixt. is dried and hot moulded under pressure. The structures are used as complex shapes to be used in fuel cells having acid electrolyte. The shapes are obtd. by moulding rather than machining, and are homogeneous and impermeable to gas and electrolyte.
A fuel cell or tank resistant to steam treatment with steam at 60 pounds per sq. inch pressure for 2 hrs having a continuous polyurethane elastomeric inner layer covered on at leaset one side with the fule sealing layer of ethylenic unsatd elastomer, the polyurethane is from one mole of polytetramethylene adipate polytetramethylene azelate, polyhexamethylene adipate or polyhexamethylene azelate, 1.6-3.5 mols of 4,4'-dicylohexylmethane diisocyanate, and 0.75-1 mol of an aromatic diamine, and the unsatd elastomer, is polybutadiene, polyisopropane, polybutadiene-isoprene, SBR, polybutadiene-acrylonitrile or EPDM. Pref. the polyurethanes contain an epoxy cpd in amts 0.5-5pts per 100 pts of polyurethane.
Cell comprises a casing contg. an electrolytic soln. contg. electrolyte and dissolved fuel, with a metallic oxide positive electrode and a negative electrode spaced apart from each other and at least partly immersed in the electrolytic soln. The electrolyte may be acid or alkaline and the negative electrode is pref. a conductive screen coated with noble metal and polyethylene graphite. As no gas is needed, for or evolved in, operation, the cell may be made completely leakproof.
Activation of silver-zinc reserve battery is accelerated to 10-12 secs. by using carboxymethyl cellulose with a degree of substitution gamma= 28-30. Alkaline cellulose (wood or cotton) is reacted with monochloroacetic acid. The product is dissolved in 6% NaOH soln. at -5 degrees C, and the soln. is used for the formation of films in a coagulating bath of 10% (NH4)2SO4 soln. followed by a 5% H2SO4 bath.
Battery comprises several cells connected in series, a common electrolyte and devices for transferring the electrolyte between the cells, each comprising two electrodes spaced apart with a position of the electrolyte between them. The common electrolyte is a non electrolyte having a conductivity 5x10-2 mhos/cm and a limited solubility for the discharge products. The electrolyte is transferred between the cells by narrow ducts of cross section limited to the point of reducing the diffusion of the electrolyte from the ducts towards the mass of the electrolyte so that in those ducts the concentration of discharge products exceeds their solubility so that the deposits which form hinder passage between the cells and increase the resistance between the cells and that the cells become isolated counteracting the major defect of such batteries, i.e. short circuiting between the cells.
Simple and economical construction of accumulators, esp. ZnBr2 accumulators, with long life, improved performance, better structural strength, flexibility, lightness and long storage life, suitable for moderate use, e.g. lawn mowers, by making the plates of 25-75 wt.%, pref. 50 wt.%, highly conducting C particles bonded by a mixture of 92 wt.% polyfluorocarbon with recurring units - (CX1X2-CF2)-, where X1 and X2 are F, Cl or H, with at least X1 being Cl or H, pref. plychlorotrifluoroethylene or polyvinylidenefluoride, the remainder being an effective amount of a polyalkylene plasticiser, i.e. polyethylene or polypropylene. The latter cpds. are used to improve the extrudability of the fluor cpds.
Acid-proof fibre yarn e.g. polyester, polypropylene, glass, of electrically non-conductive nature is coated with an electroconductive paint and lead-plated. Uniform coating is obtd., and the grids are 10 - 20% the wt. of conventional grids.
Arrangement is described for cells of different capacity which can be connected in series to different terminals. Output voltage is constant and discharge life variable, the arrangement can be used to operate radiobuoys without special timing devices.
Anode comprises a Cu or Ag plate 10 mm thick having an active area 10 x 10 cm2 coated with 0.2mm Ag halide by immersion or spraying. The cathode is of similar dimensions, made from Mg, Zn, Al etc. The halide coating improves dicharge props by removing the O2 contained in the brine electrolyte.
The cell comprises an iron anode, an air or oxygen cathode an auxiliary electrode for charging, and an alkaline electrolyte, the iron anode being pretreated with a soln. contg. sulphide e.g. Na2S. The iron electrode coated with sulphide has a longer life.
The cell has an improved capacity and long service life and comprises an anode composed of a sintered body of Fe powder contg. C fibre, an O2 or air cathode, an auxiliary electrode for charging the anode and an alkaline electrolyte.
The cell has a large discharge capacity at the anode with a relatively low wt. and comprises an active Fe anode a cathode using air or O2 as active material, an auxiliary electrode for charging the anode, and an alkaline electrolyte contng. antimony sulphide.
Rechargeable cell comprising a cathode utilizing air or oxygen as active material, an anode of active iron a supplementary electrode used for charging the anode, and alkaline electrolyte including tin sulphide.
Plate comprising core metal of titanium nitride and upper continuous member of lead or lead alloy connected with the core metal.
Iron oxide is reduced at 600-900 degrees C using H2 and the Fe powder obtd. sintered to produce material for the electrode.
Fabrication of a porous sintered electrodes for a battery or accumulator by compression of a particulate electrode material, capable of being sintered between a pir of electrodes having a lower electrical resistance than this material, which is then heated by a current supplied via these electrodes to the temp. required for sintering, so as to produce a porous electrode sintered throughout.
The holder consists of two interconnected parts one of which carries the solar cells whilst the other part is the supporting structure which can be mechanically connected to outside devices.    Pref. the supporting structure part is injection moulded from polyphenyloxide and the solar cell part is cast around the structural part in polystyrene foam.
The electrode, consisting of a hydrophobic layer and a hydrophilic catalytic layer provided with an electrical contact, for converting gaseous oxidants and fuels to electrical energy, in which the layers are made from homogenised suspns.
Copolymers contg. units -CH2-CH- (where R is H or lower alkyl, R' is same or different lower alkyl, R" is H or aryl (esp. acetyl), Y is an ion exchange gp. such as sulphonic or phosphonic acid, Z is a divalent bond or a divalent gp. connecting various chains by being bonded to C atoms, and by polyvalent radicals between the -O- atoms of the gp. (I). They have a theoretical exchange capacity of 0.5-4 meq/g. and are useful in ion exchange, electrodialysis, fuel cells, reverse osmosis etc.
Tungsten halide or oxide, tungstic acid, a tungstate of thio tungstate is mixed with a solid or liquid coking substance (pref. an organic) polymer or carbohydrate); the mixture is subjected to coking under carburising or sulphiding conditions to convert the tungsten cpd. to WC or WS2; the product is ground to obtain carbon particles in which the WC or WS2 catalyst is very finely dispersed.
Sealing compsn. for cell comprises a fluid mixt. of 40-80 pref. 50-60 pts. polyvinyl methyl ether, 10-20 pref. 15-20 pts. polyvinyl butyral and 10-40 pref. 20-40 pts. of alkyd resin. The polyvinyl methyl ether provides non-drying properties, suitable fluidity and flexibility and the polyvinyl butyral and alkyd resin provide viscosity elasticity and suitable hardness.
Process comprises filling a Zn can with a cathode mixt. through a separator, pressing the upper portion of the cathode mixt. through an upper cap member of thermo-contractible synthetic resin pref. vinyl chloride using a press and thermo-contracting the upper cap member. Process prevents electrolyte leakage and improves the properties of the dry cell.
Battery cell has a non aqs. electrolyte and Li based active cathode material with active anode material comprising 1 polymerised fluorinated hydrocarbon in which a conductive material pref soot or graphite is dispersed, the electrolyte solvent being either THF/dimethoxyyethane or THF/diethylene glycol dimethyl ether. Opt. the polymer may contain FeS or CuO. The electrolyte is LiF. The capacity in ampere hours exceeds that calculated theoretically from the propert-LiF reactions.
Porous material plus a catalyst region forms an air electrode for a cell and forms one part of a single long strip of the material.    Adjacent cells are joined by the strip, which is folded between them so that the cells are parallel in the battery.
A number of mould cores according to cells required are arranged at intervals on a carrier and the spaces between the cores filled with a fibrous reinforcing material and the material projecting above and below the spaces divided and folded around the sides of the adjacent cores and then more reinforcing material wrapped right round the whole device which is then placed in an outer form and moulded whereby the fibre material is either initially or latterly impregnated with a solidifying synthetic resin.
Process comprises mixing powdered C with powdered ethylene polyfluoride resin, forming the mixture in a mould, and heating at such a temp as will soften it until its particles are bonded. The electrode is able to resist electrolyte leakage, oxidn., and action of chemicals. The dia. of the electrode pores is easy to adjust, and therefore can be made small by varying the grain size of powdered C and ethylene fluoride resin. The electrode has great mechanical strength due to deposn. on it of ethylene fluoride resin by heat treatment. Used in, e.g., O-H gas fuel cell, air methanol liquid fuel cell and wet air cell.
Appts. includes a conveyor for moving battery cases, a clamp to hold the cases, means for supplying the battery covers, means for holding the covers over the cases, a heat platen movable between the covers and cases, means for moving the covers and cases into contact with the heat platen to soften their facing surfaces, and means for forwarding the cases and covers into welding contact upon removal of the heat platen. Pref. the heat platen is shaped to intimately contact the recesses in the covers and cases to ensure adequate heating, and the various elements are hydraulically operated. Such appts. is easily adaptable for assembly line operation.
Porous C electrodes for fuel or air cells, being light compact, of low density, with a high current density/wt ratio and a long life are obtained by mixing hollow C microbeads with a binder of a thermosetting resin or a carbonisable high -polymer material, shaping the mixture in a mould, carbonising the blank electrode by heating in absence of air and finally activating it by treatment with an oxidising agent or heating in presence of O2. The electrodes have mean pore dia. of 0.5-20 mu porosity of 5-50%, bulk density of 0.2-0.9 g-cm2, a surface/wt. ratio of 600-2,000 m2/g and a pressure resistance of 20-400 kg/cm2.
The organic fibre matrix is produced by coating phenolic resin fibres with a phenolic addition resin, forming the matrix. curing the addition resin, and making the matrix wettable by heating in air or in a partially inert atmos.
Method of fabricating a gas diffusion electrode for fuel cells, in which a powder of fluorine-contg. resin is placed on a porous plate and the powder is sintered at a temp. below its m.pt.
After one surface of a porous nickel substrate. A having a thickness of about 0.5 mm. is alternatively coated with 60% AgNO3 soln. and 20% HCl, the coating is dried to make a layer B of AgCl within pores of the nickel substrate to a depth of about 0.2 mm. A is impregnated in vaccum with a soln. which is composed of paraffin, ethylene polytrifluoride or the like and an organic solvent such as ketone. A water proofing layer C is then formed on A after drying the impregnated layer. Then when a water proofing agent such as ethylene polytetrafluoride is sprayed on the gas side of the electrode and heated, a porous layer D of ethylene polytetrafluoride is made. When the electrode is reduced by an electrolyte, the layer of AgCl may become Ag. Since the electrode comprises B consisting of Ag and Ni the Ni and the C, the discharge life may become long. Such electrode may be applied to a hydrazine-oxygen cell.
The auxiliary electrode has a separator, which is easily wettable by electrolyte, on one side, and another separator, which is hardly wetted by electrolyte but is permeable to gas, on the other. It is wound spirally round the outer cylindrical surface of the battery's element the positive and negative electrodes and the separator easily wettable by electrolyte, so enclosing the gas permeable separator.
A layer of electrolyte supporting powder is formed on the side face of a heated cathode cpd. by immersing this cpd. in a mixt of the powder and a low temp. -meltable macromolecular cpd. powder. The electrolyte supporting powder becomes pasty and swollen by a ction of the electrolyte when the compound has been inserted in a zinc can contg. electrolyte. In an example, the binding agent used for making the electrolyte supporting powder adhere to the zinc can was polyethyleneglycol.
Acid-resistant foam resin is prepd. by mixing 100 pbw. resol resin, 0.5-3 pbw. wetting agent, 1-20 pbw. blowing agent, an acid catalyst to initiate expansion, and polymerise the resin to form a coherent mass with a protective surface skin which is then removed and finally heating the mass to is approx. 150 degrees C.    The prod. is used in batteries contg. stored conc. H2SO4 to which water is added prior to use. The foam can absorb 80% of its vol. of acid while retaining its shape over extended storage periods.
The liquid absorptive capacity is increased by contacting with a liquid swelling agent at 110 degrees C and immersing in an aq. medium when the agent is other than water. The contacting increases the retained liquid absorptive capacity of the polymer by 10% greater than that which results from boiling polymer in water for 30 mins., the retained absorptive capacity being the liquid absorptive capacity of the polymer after heating at 100 degrees C for 30 mins. Pref. the polymer is in the form of sheeting. The pressure in contacting may be superatmospheric, autogenous or 0.5 kg/cm2 in excess of autogenous pressures to increase swelling.
Bibulous polymeric material, suitable for use as a battery separator in acid or alkaline batteries such as AgO-Zn comprises a copolymer of (I) methacrylic acid or mixt. of methacrylic acid plus 20% wt. of hydrophilic monomer contg. single unsatn. and (II) a crosslinking monomer contg. 2 polymerisable unsatns. or (III) a hydrophobic monomer contg. single unsatn. or (IV) a mixt. of II and III. The polymeric material has a porosity &gt;50%, pore diam. &lt;300 angstroms and a vol. resistivity &lt;20 ohm cm. The wt. ratios of the components are I : II is 125-8 : 1; I : III is 3-1.5 : 1; I : IV is 5-2.5 : 1 and ratio of II : III in IV is 5-1.5 : 1.
Containers are made from a compsn. which cures to produce a vulcanizate with a desirable combination of impact resistance and stiffness. It is useful of various battery containers and esp. for thin wall storage batteries for automobiles. The compsn. includes as an essential ingredient a resin and elastomer blend contg. 40 to 90 parts of an elastomeric base polymer and 10 to 60 parts of a reinforcing resin selected from polystyrene and styrene-butadiene copolymer resins contg. 60% styrene units in the polymers chain. The container compsn. is compounded by mixing with the resin-elastomer blend a filler, vulcanizing agent, conventional compounding agents, and mould lubricants. The resulting mixed stock is pref. granulated to produce grains of one-half inch or less in their largest dimension. The granules are then introduced into the battery case mould where are compsn. is cured at 365 degrees F.
Closed alkali electrochemical element has a plastics seal between metal components of the wall. The surface of the seal possesses a positive charge due to the presence of terminal positive gp. in the polymer of which it consists. The seal is esp. useful for nickel cadmium accumulators and is pref. of chlorosulphonated polyethylene rubber, vulcanised by means of MgO.
Separators for alkali accumulators are produced by irradiating a polyethylene film and grafting on a vinyl monomer contg. a COOH gp., by coating the polyethylene film with a soln. of a sensitiser, irradiating with UV, coiling the film onto a roll, using filter paper to insulate the layers of film, and grafting with the monomer. Consumption of monomer and of energy is reduced.
Covers for cells with acid electrolytes are produced by (a) dressing amphibole, esp. anthophillite, asbestos with a cationic wetting agent until the fibre bundles have disintegrated, (b) removing undisintegrated particles, (c) preparing a uniform suspension of asbestos fibres and fillers in the form of powder with particle size is not &gt;100 mu. which are stable in acid electrolytes, can conductions and can swell to several times their vol., and (d) treating this suspension with acid-resistant latex and making into a cover in the usual way. These covers are capable of lasting function in acid medium. Latex is based on hydrophilic (saponified) butadiene-styrene-acrylonitrile copolymer, whilst fillter may be bentonite (20-50 wt.%) or cation exchanger (30-50%).
Polyvalent phenols oxidised to qquinones before condensation with HCHO, in soln. contg. 0.05-2 wt.% dry water w.r.t. PbO, are used as spreading agents admixed to active ingredients for prodn. of negative electrodes of storage batteries. Pb sponge agglomeration is prevented, leading to improved take-off qualities, esp. at low temps. and better battery service-life; excess potential increase of negative electrodes on charging is prevented.
Construction of a two-layer laminate from two thermoplastics the first of which has a softening range (A) considerably higher than that (B) of the second particularly for producing a laminate of a polyhaloolefine and a polyolefine for use in the electrode system of a rechargeable metal halide (Zn Br2) cell, by (a) application of particles of a porous filler with an irregular surface which remain solid in the temp. range (A) to the surface of a layer of the first thermoplastic, (b) heating at least the surface contg. the filler to the lower end of the temp. range (A) to soften the surface layer and applying pressure at this temp. to embed the particles firmly but only partly in the layer so that at least part projects from the surface, and then cooling under pressure to a temp. below (A) and removing excess particles on the surface, (c) placing a layer of the second thermoplastic on the particle-contg. layer of the first thermoplastic and heating the second layer to a temp. within its softening range (B) but below the softening range (A), to bond the two layers together and then cooling below the temp. range (B).
pH of the mix will be alkaline during dischargE, and then water-soluble acrylic resin powder contained in the mix will be dissolved to sutain water in the mix and to prevent drying. So, ion diffusion into inside of the mix will be improved and reaction of manganese dioxide will be increased to improve discharge characteristics.
The cell has an acrylic resin film, which is soluble in neutral or alkaline soln. on the surface of the cathode. The stopping film on the surface of the cathode improves preservation and discharge properties.    Acrylic resin film such as Carboset 525 (RTM) has acid proofing property, and cathode mix exhibits acidic properties during preservation. So, the acrylic resin film prevents paste in the electrolyte paste layer from transferring to the cathode mix and improves the preservation property.
Cathode mixt. of cell is impregnated with vinyl monomer, which is polymerised and gelled in Zn anode can to form a polymer layer. Monomer compsn. comprises, e.g. 70 pts. water, alcohol or acetate, etc., 20 pts. acrylamide or methacrylic acid, 0.5 pts. ethylene urea bismethyl acrylamide as crosslinking agent, 1 pt. Na thiosulphate as accelerator and 1 pt. NH4 persulphate as initiator.
Cell, with zinc anode can, has pitch-sealing layer above the electrolyte paste and a layer of electrolyte leakage-preventing paper, of polyvinyl alcohol, is placed between electrolyte paste and seal. During discharge, Zn concn. of electrolyte increases, and increasing fluidity makes leakage likely. The paper layer dissolves in electrolyte as Zn concn. increases, gelling the electrolyte and preventing leakage.
40 cc. water/PTFE suspension and 300 cc. water are added to 100 g. activated carbon contg. an Ag catalyst. The slurry is well mixed and aggregated, and is heat-treated at 200 degrees C for 3 hrs. The mixt. is placed between two flexible Ni nets, the body is pressed to make a plate having a thickness of 4mm. Then the plate is heat-treated in air at 400 degrees C for 15 mins. producing a porous electrode plate having high water repellent properties. The electrode will have good polarisation properties, if it is used as an oxygen electrode. One surface of the electrode plate is coated with a soln. consisting of 15% aq. soln. of AgNO3 and 10% acetone, and is dried. This is repeated several times. The electrode plate is then heat-treated at 200 degrees C for 2 hrs., so that Ag is deposited on the surface of the electrode plate by thermal decomposition of AgNO3.
Battery comprises a cathode consisting of Pb-Sb alloy and PbO2; an anode consisting of Pb-Sb alloy and spongy lead; an electrolyte of dil. H2SO4 (roh = 1.20 to 1.30); a space within the cell; a casing made of synthetic resin; terminals; a holder to accommodate main elements, which is attached to the casing; an air electrode made of activated and water-proofed porous c, which is intended to reduce O2 in air electrochemically; a substance of felt-like impregnated with electrolyte, such as H2SO4, which consists of glass fibre, synthetic resin fibre and sponge; a hydrogen electrode consisting of porous C plate having many holes of 2-3 mm. in dia. so as to diffuse the gas, to which a catalyst metal such as Pt and Pd is added and which is water-proofed; and a lead wire to short the porous C electrode, which consists of Pt or Ta.
Prodn. comprises melting polyolefin resin such as polyethylene and polypropylene with natural or synthetic liq. hydrocarbon to make a liq. mixt., coating surfaces of a layer of fibrous compsn. with the mixt., and extracting the liq. hydrocarbon from the fibrous compsn.
Prodn. comprises forming a heat plastic coating on surfaces of a layer of fibrous compsn. by an electrostatic coating method to make a film, and applying to the film a press. and a temp. &gt; softening point of the heat plastic and below its m.pt. to make a composite porous film.
Gas electrodes for fuel cells of the type in which a porous conductive layer contg. a catalyst and an organic binder is supported on a metal foil and in which the adherence of the porous layer to the metal is improved by the formation of projections on the metal surface, pref. of the same organic material as the binder, e.g. activated charcoal and a catalyst in a PTFE binder are supported by a Ni foil. The adherence of the porous layer is improved by first spraying the Ni foil with a PTFE emulsion and drying. Using 1 mg/cm2 PTFE, well spaced asperities are formed which anchor the porous layer but do not form an insulating layer.
An amalgam anode material is prepacked into a domed, dished metal cup and retained by separator plates fitted within the aperture in a ring of elastomer material with a short inner rim, a taller outer rim and an intervening annular groove into which the cylindrical end section of the cup is secured by epoxy resin adhesive. A mixt. of HgO and graphite cathode material is retained in the lower half of an open topped metal can be further separator discs and after impregnation with electrolyte the two sections are assembled and the rim of the can swaged over the lip of the sealing ring onto the sloping edge of the cup. Leakage of electrolyte, esp. into electronic watches, is prevented.
The electrode may be produced by two processes; (1) an electrode grid of e.g., Ni, Ag or stainless steel is covered on one face with a paperlike layer of shortpolytetrafluoroethylenefibre and the fibre adhered to the grid face by sintering at e.g., 400 degrees C or (2) a gas-reacting electrode material contg. a catalyst, together with a binding agent is sprayed, painted or electrodeposited onto the electrode grid.
The mould assembly used comprises a female part having several core sections and a male part for receiving the female part. The female part is provided with tapered engaging projections and injection sprues, while the female part is provided with complementary tapered recesses at the tops of core parts, so that the both parts fit snugly. Molten resin is injected through the sprues, so as to fill a cavity. The resulting product is used as a case for a battery whereby holes being formed by the tapered projections are used for openings of the case and are closed by plugs. A bottom plate is secured to an opening of the case and electrodes are arranged in the case.
Holder for receiving a battery consisting of several electrical components, each of the sides of the elements provided with contact phases having insulations with contacts for connecting the components, and the contacts being pressed against the contact phases of the components, has contacts in the form of flat-flexible strips fastened on cushions of resilient supple insulating material, while a spring device, which is insulated by the cushions, is placed between the side of the lowest cushion in the holder which is not provided with contact strips, and the bottom of the holder. The holder is resistant to impacts and vibrations, so that short circuits do not arise, nor is the electrical connection between the different components broken. The resilient cushions pref. consist of a vinyl resin or polyethylene.
The halide is of Zn or Cd and the cell contains an internal source of halogen esp. Br depolariser within a container of polethylene or fluorinated hydrocarbon which is permeable to the halogen but shielded by the carbon electrode from the negative metal electrode. The aq. soln. forming the electrolyte impregnates the spacer between the two electrodes and may have a salt of Mn(II) added. The bromine depolariser is supplied continuously and the cell efficiency thereby improved compared to cells in which it is available only in an unstable complex.
Mfr. of a non woven felt type separator for a battery, permeable to an electrolyte comprises carding thermoplastic fibres to form a nap in which the fibres are mainly unidirectional and parallel, passing the fibres through a high temp. compressive appts. such that the fibres are oriented across the forward direction and sintering the nap at below the m.pt. of the plastic to bond the fibres together at contact points, without damage to the fibres.
A terminal seal of particular use in batteries or electronic components in which high temps. and high internal pressure may be generated, includes an external metal sleeve through which the lead terminal projects. The space between the sleeve and lead is filled by a plastics bushing placed under compression by the sleeve, axial extrusion of the bushing being prevented by two pairs of retaining rings, one pair at each end. Each pair of rings includes a first elastic ring press fitted between the sleeve and lead into contact with the ends of the bushing, and a second rigid ring pressed against the first ring to secure it in place. Such a seal can stand high temps. and pressure, and the use of the first ring obviates the necessity of exactly machining the rigid, possibly ceramic, second ring. Pref. the bushing is of polypropylene, the elastic ring of PTFE and the rigid ring of an alumina based ceramic.
Electrodes are produced by moulding a mixt. of Acheson type graphite having a particle size is not &gt;1mm. with 2-60% finely divided silicone or phenolic resin binder, at room temp. or the melting or curing temp. of the binder, and opt. heat treting at 600 degrees C to 1600 degrees C to effect carbonisation.
Device for storage cells includes a water-repellent packing layer in the space between the interior wall of the base member of the coupling device and an antil-explosive container for the Pd or Pt catalyst. The packing layer may be fibrous, cotton-like, small spherical or granular asbestos, glass graphite, synthetic resin or ceramic treated with silicon resin or fluoride resin. H2 and O2 gas generated in the storage cell reaches the space between the interior wall of the base member and the container through a plate. The generated gas is diffused into the catalyst container by the packing layer and made into steam by contact with the catalyst. This steam condenses at the packing layer, thus the water produced does not wet the catalyst or the interior of the catalyst container.
A plastic frame is used and is packed with amalgamated Zn powder.    The frame includes projections and recesses designed to allow electrolyte to circulate and ensure adhesion of the Zn. A metal terminal is also incorporated.
A membrane electrode consists of interconnected P.T.F.E. particles coated with particulate hydrophobic carbon. The membrane is shaped from a homogeneous viscoelastic dough of the carbon mixed with an aqueous dispersion of P.T.F.E., the membrane being heated to 200-325 degrees C to drive off the water to render it microporous. Such a membrane is strong and flexible, unlike prior art. membranes, and has a high degree of activity. The dough is pref. shaped into a membrane by rolling, e.g. between polyethylene release sheets.
Phenolic resin fibres are coated with ground additional phenolic resin; formed into an electrolyte matrix; the additional phenolic resin is hardened; the matrix is filled with an acid and heated, to effect oxidation of the fibre surface, and thus to render them wettable. Uniform distribution of the electrolyte is achieved because of the improved flow conditions.
The peripheral portion of the sealing plate serving as an anode collector, which is not in contact with a zinc anode, is heated and then dipped into water-repellent material so as to attain intermolecular combination between the surface of the sealing plate metal and the water-repellent material thereby forming a non-amalgamative coating layer.
The portion of the collector bar which is not in contact with a gel zinc anode, is heated and then dipped into water-repellent material so as to attain intermolecular combination between the surface of the collector metal and the water-repellent material to give a non-amalgamative coating layer. Layer may be formed of parrafin wax, polyethylene, polypropylene, polystyrene, PVC natural rubber or latex.
A zinc can (1) contains a carbon rod, cathode mix cake, electrolyte paste layer of electrolyte impregnated kraft paper, and a bottom plate. The upper opening portion of 1 is sealed by means of a synthetic resin sealing member (2). The side surface of 1 is coated with a thermo-constructive plastic tube (2) which is inwardly bent to provide good liquid-tightness with the upper peripheral portion of (2) through a packing (4) while the lower end of (3) is inwardly bent to provide good liquid-tightness with the peripheral portion of another bottom plate through another packing (5). (4) and (5) are formed of hot-melt type thermo-adhesives of inter polymer copolymer of ethylene, vinyl acetate, and wax.
A clad Zn anode for use in a rechargeable secondary cell, e.g., a silver oxide-zinc cell or a air-zinc cell, comprises an active material supporting member composed of cloth, knitted goods or a mat of electrolyte-resistant org. fibre e.g., polyamide (nylon), polyester or acrylonitrile copolymer. The support serves as a protector for the active material. A terminal is made from electrolyte-resistant metal e.g., Ni, Fe or Ag. End portions of electrolyte-resistant material, e.g., synthetic resin or ceramics, cover both ends of the active material and the support member. The active material is spongy metallic Zn produced by redn. of moulded ZnO powder contg. Hg oxide. A ceramic separator is interposed between the active material and the support. The separator is produced by sintering alumina or alumina silicate powder contg. alkali (ne earth) metal oxide, and prevents diffusion of Zn acid ions. A conductor is axially positioned in the cell.
The cells have large output per volume as well as per wt. and consists of a composite cathode, a porous anode and caustic alkali electrolyte containing zincate. The cathode construction is such that, over the whole surface, adjacent to the electrolyte, is a first porous layer which is composed chiefly of activated carbon and where air depolarization takes place, and a second layer which is of a substance capable of being electrochemically reducted at a potential equal to or slightly higher than, that of the air electrode, the second layer working chiefly in the initial stage of discharge.
The positive electrode is formed by a paperlike fibrous substance which is composed of either natural fibre, such as pulp or linter, or synthetic fibre such as acryl or nylon, and is attached to a powdered cathode depolarizer, such as CuCl or Cu oxalate, and an electroconductive agent such as graphite or powdered metal. The positive electrode covers a negative electrode, which is a Mg plate, with a synthetic resin separator placed between in such a way that the separator covers the whole of both front and rear sides of the negative plate. A layer of these elements is folded back in the shape of a U.
Closed circuit breathing system for e.g., aircraft pilots includes a permselective membrane gas separator using an immobilised liquid film, which must be retained in damp condition, together with a solid polymer electrolyte fuel cell to which electrical energy and moist air are supplied. The fuel cell preferentially transports pure O2 across the solid electrolyte for use in the breathing system as make-up O2 for purified exhaled air, which has been circulated over one side of the permselective liquid membrane area of the gas separation device. Moist gaseous exhaust of controlled rel. hum. from the cell is used to scrub and dampen the opposite side of the membrane.
Cell comprises an oxidation electrode of sintered nickel contg. Ag catalyst, a fuel electrode of sintered nickel contg. Pt catalyst, an electrolyte of 30% caustic potash contg. 5% hydrazine fuel, an oxygen chamber, and an electrolytic cell. A separator composed of porous sintered nickel plate contg. Pt catalyst and an ion permeable film of, polyvinyl-alcohol, diposed on the fuel electrode side of the porous plate is arranged between the fuel electrode and oxidation electrode.
Battery container with thin walls (&lt;0.10 in. and with taper &lt;0.0025 in./in.) is injection moulded in mould having a first section forming the outer portion and several cores to form the walls by rigidly connecting bottom of core to first section, injecting material, unfastening connection before thermoplastics sets, removing alternate cores after initial hardening period, separating remaining cores from first section, and removing plastic from cores.
Short-circuits in an alkaline Ni-Cd accumulator with laminar electrodes are eliminated by arranging the canned electrodes with joints facing each other in a pile, topped by a metal cup fixed to the housing. Plastic spacers are fitted between the positive electrodes and the cell separators.
Alkaline cells with a cathode of HgO have a multi-component separator between anode and cathode comprising an electrolyte-sorptive mat of cellulosic fibres in contact with the anode, an oxidation-resistant mat of fibrous synthetic polymeric material in contact with the cathode and between each a non-fibrous film of electrolyte-permeable material pref. polyvinyl alcohol. The separator prevents internal shorting and has high degradation resistance.
Duplex electrodes, structurally bonded with each other by continuously support strip, have each electrode composed of a segment of support strip with a positive electrode on one side and a negative electrode on the other side of this segments. The support strip is provided with both intermittent positive and negative electrode deposits, the negative electrode deposits being placed on the other side of the support strip almost opposite the positive electrode deposits. Used in the prodn. of multicell batteries. The support strip enables the electrodes to be fitted into batteries without removal from the substrate on which they are deposited. The flexible continuous strips can be easily used on high speed prodn. machines.
Fuel electrode for a rechargeable cell esp. of the metal air or metal oxygen type or the alkali electrolyte type and having a first porous layer covering it on which the electrochemical reactions are effected during discharge characterised in that a second more finely porous layer is provided on the first layer at the level of which oxygen is released during charging. Opt. a third porous stopping layer contg. very fine pores is provided. The second layer prevents access of the oxygen to the reacting layer during charge, so that the life of the cell is increased. Pref. the first layer is formed of particles of active carbon or catalyst-coated carbon opt. cohered by PTFE.
Copper sulphide base electrode for anode cell using non-aq. electrolyte, is made by mixing CuS with a powdered plastic, a pore former and opt. an electrically conducting powder to improve the electrical conductivity. The mixture is then heated to sinter the platic into thin flexible sheet so that the electrode can be coiled into a coiled electrode formation. Prior art. CuS electrodes could only be made in rigid sheet form.
Electrodes for fuel cells, having better resistance to O2 and to embrittlement by H, better resistance to wetting even after long use and better electrical and thermal conductivity, consists of two layers. The first consists of pyrolytic C coated carbonised paper impregnated with 25-80, pref. 60 wt % of a hydrophobic plastic pref. PTFE. The second layer consists of a hydrophobic plastic, pref. PTFE, and a catalyst. This layer in an O2 electrode consists of 75 wt % Pt and 25 wt % PTFe and is 4 mg/cm2 thick, while in an H2 electrode it is 2 mg/cm2 thick and consists of 32 wt % Pt, 32 wt % Rh, 16 wt % WO3 and 20 wt % PTFE.
Method comprises dissolving a synthetic resin in a hydrocarbon solvent, coating the desired parts of the metal with the soln., then dipping the metal parts in an organic soln. that does not dissolve the synthetic resin and is compatible with the solvent, and crystallising the synthetic resin into fine crystals and heating them and forming a synthetic resin film.
Porous electrode for a fuel cell, usable with acid electrolytes, consists of a foraminous metal support an inert hydrophobic polymer (pref. PTFE) bonded to the support, and an outer coating of catalytic material consisting of a polymerised phthalocyanine polymer on an inert finely-divided support. This catalyst gives improved yields for the electrodes.
Dry cell battery packing unit is moulded from foamed polystyrene in the form of a plate which is provided with an array of recesses adapted to receive the batteries with a push-fit, the depth of the recesses varying from 5 to 35% of the height of the batteries whose tips are covered with shrunk on polyethylene foil.
Each cell of a primary metal-air battery has two electrically connected air electrodes, arranged on opposite sides of a metal anode and insulated from it, which include catalyst material. They are carried by porous strips of PTFE which are joined at the rim by ultrasonic welding to form cell chambers each containing air electrodes and an anode.
Method comprises mixing carbon with a binding agent of a linear polymeric hydrocarbon which is dissolved in a mineral oil, hot rolling the mixture to form a conductive film and thermocompressively bonding the conductive film to a zinc plate through the mineral oil layer. Oxidn. of the Zn plate is reduced, giving a time stable electrode resistance.
Method comprises mixing carbon with a binding agent of a linear polymeric hydrocarbon and which is dissolved in a liquid paraffin, hot rolling the mixture to form a conductive film, and thermocompressively bonding the conductive film to a zinc plate through the liquid paraffin layer. The presence of liquid paraffin layer on the zinc prevents the surface being oxidised, giving less variation of electrode resistance with time.
Cathode includes conductive material e.g. acetylene black, carbon black or graphite and cathodic active material of metal oxide, bonded by polyisobutylene. Polyisobutylene has no unsatd. bond and is very stable to strong alkaline electrolyte. Pref. mol. wt is 3000 to 200000.
Cell comprises a cathode of Cu, electrolyte of brine contg. ammonium sulphate, chloride or nitrate, and an anode can of Mg or Al. The cathode is enclosed in a porous paper.
Cathode mixture was made from (parts 700 MnO2 and 100 graphite mixed in dry state. About 3.2% of PVA polyvinyl alcohol soln. as binder consisting of 16 PVA and 480 water was added to make a slurry. The slurry was sprayed using a nozzle under pressure of several Kh/cm2 into a drying room to obtain dried grain powder of uniform grain size and spherical shape.
A composite electrode for an electrochemical cell is made by (a) introducing 0.5-7 mg/cm2. particulate electrocatalytic material uniformly through a fibrous polyfluorocarbon matrix and (b) heating to a temp. high enough to bond the catalyst to the matrix. The fibrous mat is made by (i) pptg. a polyhydrocarbon dispersion onto a loose slurry of oppositely charged cellulose fibres, (ii) shaping the mixt. and (iii) heating to burn out cellulose fibres and provide a matrix of controlled porosity, and preselected aq. wettability.
Paper produced by the conventional method from fibrillated fibres made from an acrylonitrile/vinyl acetate copolymer (ratio 95-85 to 5-15) ground to 25-40 degrees SR, has sufficiently hydrophobic props. to be used without the usual hydrophobic treatment as the matrix (subsequently platinized) for the electrodes of hydrogen-oxygen fuel cells.
Air diffusion electrodes for use as plates in accumulators have on the surface of the layer towards the electrolyte an electrically conductive coating which facilitates the penetration of the electrolyte and is electrically connected to a current collector and to the catalyst-containing layer. Electrically conductive coating and the latter are connected in parallel. The layer towards the electrolyte canbe the catalyst-containing layer (with PTFE as the binder) or in inactive layer forming a cover (made of finely porous asbestos).
An electrically conductive fluorocarbon polymer is prepd. by (I) immersing the fluorocarbon polymer in a liquid metal fluoride such as rhenium or molybdenum hexafluorides for a sufficient time to allow penetration of the polymer by the liquid (II) hydrolysing the metal fluoride by subjecting the polymer to a water bath at 100 degrees C or by dispersing it in a water vapour-contg. gas. Prefd. polymers are PTFE, chlorotrifluoroethylene, vinylidene chloride and fluorinated ethylene propylene and are spongy. These polymers are particularly useful as electrode coating in electrochemical cell to give very long cell life and can be used to coat surfaces in e.g. operating theatres where otherwise there would be danger from explosive atmosphere.
A fuel cell electrode is made by adding an acid, pref. H3PO4, to a mixture comprising supported catalyst-containing particles, a reactive material exothermally reactive with the acid and a polymeric thermoplastic. The acid mixture is heated sufficiently to set off the reaction between the acid and the reactive material causing the polymeric thermoplastic to become fluid and adherent. The heated mixture is subjected to pressure to complete the bonding.
Method for bonding together components, one of which is of porous resin, esp. a non-weldable hydrophobic resin such as PTFE, consists of bringing this first porous component into contact with a second component of material having a lower m.pt., esp. a weldable material, and melting the second sufficiently to make it flow into the pores of the first without melting the first, then cooling to set the bond. The system may be used to form a sealed multilayer bag around a metal electrode for a primary metal/air battery.
Separator is produced by treating aq. suspension of flour or starch and alkali with 0.5-7% POCl3 and alkali, w.r.t. glucose, within 1 hr. keeping pH&gt;10, and then with ZnCl2. NH4Cl when reaction is complete. Gel film on the separator does not liquefy during discharge. These elements give higher storage capacity and can be produced simply and quickly.
Rechargeable cell of improved potential and energy density has non-aqueous organic electrolyte, solvent and a barrier membrane of ultrafine porous polymer separating anolyte and catholyte; the membrane comprises a solid thermoplastic polymer of a monoethylenically unsatd. hydrocarbon pref. polyethylene of porosity is not &lt;40% provided by uniformly distributed interconnecting pores of dia. 40-120 angstroms.
An electrode comprises a powder mixt. of a metal and one of its salts in a matrix of hydrophobic polymer applied as a non-pressed coating to an electrically conductive substrate.    In electro chemical applications, for measurement of potential, passage of current e.g. in chemistry, bio-medicine etc. The cost is reduced, as the conductive substrate need not be of the electrode metal as it is prevented from contacting the electrolyte by the hydrophobic polymer. In pref. embodiments, the impedance and motion sensitivity of the electrode are low.    The matrix material may be a mixt. of hydrophobic and hydrophylic polymers and/or a second coating may be formed over the first coating, the second coating comprising a metal-metal salt mixt. in a matrix of hydrophilic or a mixt. of hydrophobic and hydrophilic polymers.
In the prodn. of electrodes for galvanic cells, the binder particles on the surface separate as a hydrophobic film by immersing multi-layer electrodes in solvents and then evaporating the solvents; the hydrophobicity varies continuously over the cross-section of the electrodes.    In fuel elements and hybrid systems.    The hydrophobic layer is not easily removed from the surface of the electrode by the electrolyte. Large amts. of binder are not needed.
The support, which is located in the floor of a battery casing, consists of a grid having parallel spaced apart rails upon which the battery plates rest and cross bridging members interconnecting the rails. Both the rails and the bridging members are formed in their lower edges with arches through which circulation of the battery liquid is possible. This circulation allows an even deposition of mud to occur over the lifetime of the battery and prevents premature shorting between plates when the mud has built up locally and extends between the plates. Pref. the support is moulded of glass reinforced polyethylene.
Microporous film or PTFE is made by forming an aq. homogeneous dispersion of particles of PTFE and another water-insol substance (I) which does not precipitate or coagulate the PTFE, casting a film of the dispersion drying and sintering it, rolling it to form a fibrous structure and finally removing the particles of (I) pref. by leaching or dissolving. (I) is pref. Zn, Cd or Ag or their oxides, lead oxide, lead carbonate, silica, or glass fibres. The porous film is strong and flexible with uniformly distributed pores and high ionic conductivity.
Zinc dendrite formations inhibitor is an organic cationic polymer of repeating units which in aq. soln. form positive ions of formulae :- where A and B are H, alkyl or phenyl substd. by hydroxy, amido, carboalkoxy, lower alkoxy, phenoxy, naphthoxy, cyano, thioalkoxy, thiophenoxy, lower alkyl, 5 or 6 membered cyclo-alkyl, tri(lower alkyl) ammonium lower alkyl, and an alkyl only a nitro gp., or an phenyl a halogen atom, or A and B together can be -CH2-CH2-, -CH(CH3)-CH(CH3)-, -CH=CH=CH-, -CH=CH-CH=N-, or -CH=CH-N =CH-, R and R' are H, Cl, Br lower alkyl or phenyl, X is -CH2-(O)n- (CH2)m-, Y is -(CH2)p-(O)n-CH2-, Z is (CH2)p-(O)n-(CH2)2- where n is 0 or 1, m is 1 or 2 p is 2 or 3. Ions are pref. monovalent dialkyldimethyl. NH4OH polymer.
An electrode for an electrochemical cell esp. a metal/air depolarised cell, comprises an electrocatalyst and a fluorinated phosphonitrile polymer. The polymer may be of the formula where n is 3, R is F, fluorinated 1-10C alkyls, fluorinated mononuclear aryls, amino or thio contg. derivs., fluorinated alkoxy, fluorinated aryloxy or mixtures, and R' is the same as R or a halogen or halogenated derivative or alkyl, alkoxy, aryl aryloxy gps. The electrocatalyst is pref. Gp VIII or IB element, mixture or alloy, and may be mixed with the polymer or coated onto it. The mixt. may be self supporting or supported on a hydrophobic fluorinated phosphonitrile polymer or PTFE membrane.
The top of the side wall of the Zn cathode is below the level of the top of the MnO2 depolarizer/ZnCl2 anode assembly from just above which the side wall of the separator is splayed outwards and fixed to the inside wall of the above inner can of polyethylene, polypropylene, vinyl chloride or the like. This prevents the forcible expulsion through the plastic of the inner can of liquid collecting above the top of the depolarizer sac due to the pressure of hydrogen liberated at the depolarizer.
Conducting film is laid on the glass surface and an electrode applied. The electrode is covered by an intermediate film, on which is then placed another layer of glass. The assembly is fixed together in an autoclave. Pref. electrode is made from Cu or Cu/Be alloy, 0.05-0.2 mm thick.
Separator for lead acid accumulators made of glass fibre reinforced synthetic binder - polymethylmethacrylate latex (with the addition of starch) wherein for improving the gas permeability, the separator is emulsified with 3-11% sulphonated product of polyethyleneglycol ester alkylphenol. The separator has low elec. resistance and contains negligible Cl ions.
Fuel cell electrodes for use in acid medium comprising W impregnated C-granules compressed together with a plastic binder.    C granules are impregnated with ammonium orthotungstate and fired at 750-950 degrees C in a reducing atmos. 5-35% (pref. 30) of 150 mu particles of polytrifluorochloroethylene (VOLTALEV 302 UF(RTM) Soc. Ugines-Kuhlmann) are added, the mixt. compressed at 40 kg/cm2, heated at 320 degrees C/15 mins and cooled under pressure.
Fuel cell electrode prepd. by coating sintered Ni with a mixt. of a metal and a fluorinated polymer from a liq. suspension, followed by application of a porous polymer film under pressure. The assembly is then heated at 100-400 degrees C in H2 or H2/N2 to drive off the remaining liq., bond the layers together and reduce and activate the catalyst. Pref. catalysts are Pt or Pd black, Raney Ni or Ag or their mixts., and the polymers are pTFE, PTFE-propylene, or polytrifluoromonochloroethylene. The suspension is applied by spraying onto a hot (20-300 degrees C) sintered plate 0.05-0.5 mm thick, the porous polymer foil is applied at room temp. and 50-200 bars (pref. 100).
An elastic casing esp. of polyethylene, with a gas permeable membrane in one wall has an anode in the form of Mg strips laid in the folds of a "w" shaped porous separator to the opposite side of which MnO2 cathode material and collector material are applied in alternate folds. The activating liquid, an aq. soln. of KOH, is in a polyethylene bag broken by pressing/squeezing or by bending and this bag is separated from the membrane by a labyrinth seal of overlapping layers of polyethylene welded to the inside of the casing along their edges. The membrane is of heat welded fibres of polyolefines.
Title electrodes contain mixtures of carbon black with chelate metal complexes derived from salicylaldehyde or its homologues and a diamine (Pfeiffer's complexes), pref. polymeric cpds. contg. a transition metal atom (pref. Co) as the central atom. They are highly resistant against hot H2SO4, and have high catalytic activity.
The electrode as in parent patent has a porous, water repellent, non-conducting layer faced on both sides with a conducting layer but the porous layer possesses no through passages other than its pores and has a portion of its surface exposed so that it is in direct contact with the electro-active gas of the cell or generator. The porous layer is considerably decreased in thickness making the whole assembly more compact and less brittle and is pref. of PTFE mixed with metals and/or activated carbon PTFE is used facing layers.
Solid electrolyte cells are used for gas analysis by passing a current proportional to the cell potential through a potentiometer to a compensating recorder. The potentiometer is adjusted to interchangeable scales on the recorder at a constant arbitrary cell temp. by a pure gas introduced in the cell as the gas to be analysed or at constant voltage source inserted instead of the cell potential. The recorder is set by varying the potentiometer to the known compsn. when a know gas is used or to the voltage marked on the scale for the temp. concerned when a constant voltage source is used.
The aqs. coating compsn. comprises a siloxane-modified resin in a water-miscible organic solvent, all dispersed in water in the form of a salt of the resin with a nitrogenous base. The resin is an addition copolymer of hydroxyl functionality at least 15, an acid value of 12-100 and comprises mainly a C1-C4 acrylic acid ester. The organopolysiloxane has the formula: (in which R is a monovalent hydrocarbon; R1 is an alkoxy or OH radical; n has an av. value 1-2; m has an av. value at least 0.1 and m+n is an av. value of least 0.1 and m+n is not more than 3). The organopolysiloxane has, on av., at least 1.2 R1 gps. her molecule, comprises 2-30% by wt. of the resin and is condensed with OH gps. to eliminate 10-90% of the water or alcohol of reaction from its functional gps. to incorporate it in the form of an ether. It is particularly suitable for electrodeposition on the anode of a D.C. system, the silicone giving gloss and weather resistance. Deposited films may be baked to provide solvent resistance.
Casing for sea water activated battery,is formed round a stack assembly of spaced electrodes by dipping into a molten plastic for an inner skin to form and further wall material to solidify on withdrawal. Manifold passages for ingress of sea water electrolyte are formed across the edges of the stack by cores which are later removed.    Pref. the stack is held for dipping, between upper and lower horizontal core arms which have vertical extensions. Portions of the casing at the corner edges are later cut through to open the ends of the manifolds and separate the vertical arm extensions and allow the horizontal cores arms to be removed. Casing is pref. of cellulose acetate butyrate. The manifolds limit inter cell leakage through the water by acting as hoods.
Air/metal fuel cell electrodes are covered with an additional layer comprising a hydrophobic material permeable to air and on the 'air' side of the electrode. Pref. the extra layer comprises a sheet (about 0.5 mm thick) of sintered PTfe or of PTFE mat, impregnated with particles from a PTFE suspension of emulsion and consolidated at about 40 kg/cm2 while cooling after sintering for 15 mins. at 320 degrees C. Used to prevent any permeation or exudation of electrolyte right through the electrode.
Ethylene oxide polymer is added to soln. zinc-contg. electrolyte in a rechargeable galvanic cell having a Zn anode to suppress formation of Zn dendrites on the anode during charging. Polymer is selected from di-, tri- and polyethyleneglycol of 200-6000 mol, wt and their 1-4C alkyl and alkanoate esters, in a pref. amt of 0.01-10 wt.% based on electrolyte. The additive may be used to extend cycle life in alkaline or acid electrolytes.
The electrode is obtained by compressing a mixture of Cu, CuCl2, a synthetic binder and a pore forming agent and heating between 150-350 degrees C in an inert atmosphere. Pref. compsn. consists of 5% Cu, equivalent quantity CuCl2, 35% PVA or PTFE based binders, 10-30% camphor. Heating conditions are 180 degrees/1 hour for PVA, 250 degrees/1 1/2 hrs. for PTFE. Used as cathode in cells with Li anode and LiAlCl4 in methyl chloroformate electrolyte.
Composite electrode of active material (metal or metal oxide) dispersed in a polymer gel or resin exhibiting selective ionic conduction. An electrical conductor such as graphite may be added. Prefd. materials are Zn and PVA and the polymer acts as a barrier to zincate ions while exchanging OH ions with the electrolyte. The structure prevents electrode disintegration and dissolution in the electrolyte and maintains the pH near the electrode.
Seal is for connection between electrodes and battery connections of an electrolytic element. A springy seating has holes for the connections; deformable, electrically conductive parts are inserted in the holes and are pressed against the seating to form a liquid between both parts.
An opening in the cell case housing electricity generating element is sealed with a sealing material made from synthetic resin; the upper end of a carbon rod constituting the positive electrode collector of the element projects outward piercing the sealing material; the rod is fitted with a positive terminal cap on the top; and a solid or fluid-state packing is between a flange extending radially from the lower end of the terminal cap and the upper face of the sealing material. Used of the packing enables the ventilation between the cellhs interior and outside to be perfectly shut off, and thereby prevents the gas in the cell from escaping through the carbon rod. The packing also prevents the electrolyte from seeping out of the cell following the gas discharge therefrom, and the positive terminal cap from corroding.
A mixture of high purity powdered active C (purified by treatment with HF acid), a water-proofing agent and a binder are applied to one surface of a sheet of carbon fibre cloth or felt to produce a thin electrode.
Prodn. of gas diffusion electrode for ait-methanol, air-hydrazine, oxygen-hydrazine, fuel cells, etc. by roughening the surface of a porous electrode body, and applying powdered fluorine-contg. resin to the roughened surface.
Prodn. of gas diffusion electrode by adhering a porous resinous film to the gas side of a porous electrode substrate by pressing, and simultaneously compressing the electrode substrate. By this treatment, leakage of liquid to the gas side is prevented.
Fuel cel contg. a liquid fuel e.g. methanol, ethanol and formalin and electrolyte of metal salts contg. CO32-ion (e.g. K2CO3), is characterised in that the fuel electrode comprises a powdered stainless steel, a powdered carbon, a resin binding agent and a catalyst. The fuel electrode has durability, resistance against electrolyte contg. CO3-- ion, and improved mechanical strength.
The upper portion of the carbon electrode is treated to have improved water-repellent properties w.r.t. that of the lower portion of the electrode. As the result, the penetration of the electrolyte is decreased at the upper portion and made uniform all over the electrode, which improves the lifetime of the electrode.
The stacked laminate cell is placed in a cylindrical container so that an annular space is left between the stack and cylinder walls. Resin is introduced at the top of the cylinder which is revolved about its axis forcing the resin over the top of the stack centrifugally, thus forming in the annular space a protective layer over the sides of the laminate stack of uniform thickness. The resin prevents circulation of electrolyte between two adjacent cell units.
The cell conventionally comprises a water-proofed porous carbon air electrode, zinc-coated nickel or stainless steel net electrode, electrolyte of KOH contg. plumbic acid ions. The conventional Ni mesh auxiliary electrode additionally has 0.2 mg/cm2 Pd, which improves the working characteristics of the cell.
A thin, porous regenerative sheet for an alkaline primary battery, esp. a zinc-air battery comprises colloidal lime particles (pref. 75-95 wt.%. 0.01-1 mu particle size) and up to 25 wt.% dispersed cellulose fibres bonded with a swellable, alkaline insol. organic binder. The binder may be insolubilised hydroxy-ethylcellulose, precooked starch, plyacrylic acid, polyvinyl alcohol, polyvinyl formal or polyacrylamide resin. An aldehyde cross linking agent, pref., formaldehyde may be included to control binder swelling. The sheets may be prepd. by casting a slurry of lime, cellulose and binder and drying.
A permselective inter electrode separator comprises layers of a pellicle forming, undehydrated layered silicate of at least one of Na, Al, Cd, Cm, Y, Nd, Gd, Ce, La, Ca or Eu. insol. in the electrolyte and saturated with chemically bound H2O and OH. The synthetic resin binder, pref. PTFE, may be included and the separator may be self supporting or coated on an electrode. The separators may be used electrolytes, have low ohmic resistivity and are resistant to shorting due to metal deposition.
Anisotropic porous membrane of polysulphone polymer having repeating units of diphenylene sulphone comprises microporous barrier layer 0.1-5 mu thick having porosity 1% by volume, effective average pore size 20-100 angstroms, and a macroporous support layer having 50-80% voids by volume; the membrane having been treated with oxidising acid (pref. nitric acid). It has high moisture vapour transmissivity, ease of water absorbtion, and is non permeable to H2, O2, N2 etc.
A rechargeable metal/air or O2 depolarized cell comprises a composite cathode with a hydrophobic membrane exposed on opposite surfaces thereof to an oxidant and an electrocatalyst respectively. A bi-porous unit has its coarse pore face contacting the electrocatalyst and its fine pore face contacting a bubble carrier. A consumable anode is in contact through an electrolyte with all these components when the cell is on load. However, when the cell is being recharged electrolyte is evacuated from the coarse pore face by gases formed at the fine pore layer thus removing electrocatalyst from contact with the electrolyte.
A positive gas diffusion electrode for an alkaline electrolyte fuel cell is wet proofed and has most of its surface inside the cell casing covering with a fuel- and oxidant impervious mask. The rest of the surface forms an interface with the electrolyte and is coated with a water sol. polymeric thickening agent swellable in the electrolyte, pref. a carboxy polymethylene polymer. Part of the electrode outside the casing contacts an oxygen oxidant. Alcohol as fuel is dissolved in the aq. electrolyte soln., which also contains an alkali metal silicate. A negative electrode is spaced from the diffusion electrode. The formation of an alkali carbonate crust on the outer surface of the positive electrode, alcohol evapn., and electrode flooding are all minimised.
Iron oxide and/or iron oxide hydrate particles with a fused, non chemically reacted additive coating of elemental S, Se or Te are slurry coated onto a battery plate for use in e.g. nickel iron battery using aq. alkaline electrolyte. The additives does not separate during slurry coating or battery operation. The particles are coated by heating a mixt. of the iron oxide component and 5-20 wt.% additive in a container pref. lined with PTFE, that allows gas leakage, to a temp, near the additive m.pt., i.e. 100-150 degrees C. for S.
Battery boxy and recessed lid are secured by positioning box and lid with opposed dies and putting a heater in between to contact an internal shoulder on the lid, the heater being recessed so that id does not contact the wall of the lid adjacent the shoulder. Pref. the wall forms with the upper tapered portion of the box wall a tapered recess into which molten material flow when the lid and box are pressed together after the heating. Polypropylene is pref.
A device for simultaneous circulation of a liquid and a gas and regulation of the gas pressure, consists of a rigid vessel divided into two compartments by a flexible membrane, impermeable to gas and liquid, the first compartment being joined to liquid entry and exit ducts, each provided with a non-return valve, a spring acting on the membrane to increase the volume of the first compartment, the second compartment being joined by gas entry and exit ducts, the entry duct being associated with a spring operated valve arranged so that when the volume of the first compartment increases the membrane pushes the valve spring so as to permit entry of gas. The device ensures good circulation of electrolyte and a controlled gas upply pressure to a fuel cell. The non-return valves consist of diaphragms of elastomer, pref. neoprene, inserted between orifices in a series of plates. The spring acting on the membrane may be a corrugated sheet.
The powdered polyphenylenesulphide resin at 10-40wt.% is mixed with a bulking material of nickel, graphite, carbon, Mg, Al, Cu, Ta, Fe, Ti or Ag. The mixture is preheated to a point just below the resin's melting point, and poured into a preheated mould. Pressure is applied at 211 kg./cm2 and the temp. raised to a point above the resin's melting point. After cooling, while the pressure is maintained, the body is removed from the mould.
Process is characterised by pasting a kneaded mixture of an aqs. suspension of PTFE resin with powdered activated carbon on a metal net, etc. drying the pasted sheet at 200-300 degrees C so that it forms an activated carbon aggregating cloth, and causing a water-repellent and gas-permeable synthetic resin film to adhere close to one side of cloth by applying pressure. The present invention is for providing gas-diffusing electrodes with high mechanical strength stable and with long life.
The lead electrode, esp. the anode of a lead acid accumulator is sheathed in a porous, synthetic, oxygen and acid-resistant material, formed from two or more layers of synthetic material in sheet, fabric or fritted form in the shape of a bag, tube or pocket, whose inner surface is coated with a conducting agent resistant to oxygen and acids. The method provides a convenient means of enclosing the electrodes to prevent the active material forming a sludge, and of eliminating separators. Polyethylene, polyesters or fluorocarbons are suitable for the sheath.
For use in alkaline storage batteries, partic. those having electrode system such as Ni, Cd, Ni, Zn, Ag, Zn and MnO2-Zn, in which the separator must be highly resistant to physical and chemical influences within the cell. Novel construction comprises at least two bibulous, non-membraneous separator layers laminated together with a thin layer of a gelling agent, which provides mechanical integrity to the separator layer and functions as a semi-permeable membrane. Alternatively the separator comprises bibulous, non-membraneous separator layers sandwiching and laminated to a membraneous layer utilising a gelling agent to provide an integral separator of mechanical integrity. These separators have particular utility as inter-electrode spacers in alkaline batteries in which a separator resistant to alkaline electrolyte, oxidation, dendrite growth and other degrading cell environmental factors are required.
The cathod comprises a metal plate, electroconductive film formed    on one surface of the metal plate, and past layer formed on the other, the paste being composed of a mixture of water-insol. polymer and paste material.
The composite plate is produced by mixing electroconductive material into an adhesive base comprising e.g. a polyamide resin, dissolved in an organic solvent system. A further soln. is prepd. by dissolving e.g. an epoxy resin in the same solvent system. The two solns. are mixed to form a uniform soln. which is applied to a metal plate. Heating is carried out to form a film on the plate surface.
Method comprises placing a net body on a metal plate e.g. Zn or Mg, painting electroconductive epoxy resin on the metal plate through the net body, rmoving the mesh body, and heating for baking the epoxy resin. The object is to provide an improved zinc-carbon combination electrode having painted electroconductive film of uniform thickness and of small resistance.
Method of fabricating a combination electrode plate for a battery by painting epoxy resin as paint base, polyamide as hardening agent, carbonic material, and formic acid onto a cathode metal plate, and heating for baking the paint.
Method of charging rechargeable batteries each provided with an electrode for gas depolarisation, such as those of air-zinc, oxygen-zinc and air-cadmium types. The method is designed for charging batteries of the abovementioned types, each provided with a gas depolarising electrode and rechargeable negative electrode, both of which are obtainable by adding a catalyser to their base material produced by sintering an alkali resistant and electrochemically stable powdered metal, and then subjecting it to water-proofing; the method being characterised in that the negative electrode is to be charged as the gas depolarising agent is being supplied by compression, the gas depolarising electrode acting as the counter-electrode. The abovementioned powdered metals include Ni, Ag, Fe, etc., and the catalyser is Pt, Pd, Ag or activated carbon.
A sheet of PTFE fibres is integrally fitted to a metal mesh (e.g. of Ni) and the whole is sprayed or pasted with a mixture of powdered C and/or metal with synthetic resin binder.
An intermediate substance between vinyl acetate and PVA, whose saponification value is from 40-75, is adhered either by itself or mixed with a water-swellable or water-sol. paste, to the inside of the negative zinc can be preheated to a temp. above the m.pt. of the intermediate substance and interior is then filled with further power-generating elements.
Galvanic cell has a gas vent formed by a liquid impervious, gas permeable, hollow fibres e.g. of polypropylene, arranged in the galvanic exterior of the casing.
A storage battery includes a core and a one piece moulded polypropylene cover, the cover including a vent well extending into the case and provided at its lower end with a baffle plate and at its upper end with a passage passing through the cover, and a series of filling wells also projecting into the case. The region of the cover around each well is recessed and accommodates a closure flap hinged to the cover plate at one edge of the recess and provided on its underside with a plug adapted to close the well when the flap is pressed into the recess. Such a plate allows ready servicing of the battery, is pleasing to the eye and avoids manipulation and possible dropping of conventional closure plugs.
A porous, rigid, inorganic separator is coated with a flexible porous film comprising a major part of inorganic material and a minor part of potassium titanate fibres bonded together with cured organic polymer, sp. polyphenylene oxide with polypropylene polyazelate of average mol. wt. 850-6000, and polysulphone. The flexible film remains intact when the rigid separator cracks, increasing battery life. Esp. suitable for high energy density silver-zinc alkaline electrolyte batteries.
Glass film mats, impregnated with acid resistant adhesive are wound into multi-layer tubes around cylindrical mandrels as in parent patent cell capacity and life are improved by the use of water suspension or soln. as binder adhesive. The suspension is of finely powdered copolymerised vinyl-chlorides and vinylidchlorides, the vinylchlorides being 30-70% of the whole. Alternatively a starch soln. may be used.
Autoxidation of the finely divided very active catalytic materials used as electrodes in fuel cells is inhibited by coating the catalyst material immediately after prodn. by a material giving protection against oxidn., dissolved in methanol and removing the alcohol by evapn. The protective material is pref. hydroquinone, metaldehyde or polyoxymethylene. The protective coating is removed before putting the electrode in the cell by rinsing with alcohol or by circulating the alcohol in the cell compartment after installing the electrodes.
Process comprises a synthetic resin casing covering the opening end and the side of a zinc casing, and embedding the bent opening end of the zinc casing into the sealing portion of the synthetic resin outer casing by pressing on the bent end from the outside.
Process comprises mixing one electrolyte, contng. dissolved acrylamide with the other electrolyte, in which an agent for initiating polymerization of the acrylamide is dissolved, pouring a mixture of these two electrolytes into the anode zinc can which has a water soluble paste layer formed on the inside; and then inserting the cathode compound into the cell, so that a layer resulting from polymerization of the pasty electrolyte layer and acrylamide may be formed between the cathode compound and the anode zinc can.
Battery has a terminal post disposed wholly within its container of thermally deformable material and located adjacent a container wall. A metallic terminal insert defining the battery terminal has a stem passing through the container wall and embedded in the terminal post. The container wall material through which the insert passes is locked between a part of the insert and the terminal post. Such inserts may be installed automatically by a method combining high-speed rotation and pressure.
Protector permits excape of gases and retains electrolyte entrained by the gas. TIt prevents short-circuits, between the upper parts and heads of the plates and/or the junctons of opposite plarity, during ageing of the battery. The rectangular sheet of electrolyte-resistant insulating material has small holes in its central region, and notches on 2 opposite edges to leave tongues which are placed between the plate heads.
Air electrode for air-metal cells comprising three layers:- the first containing carbon black, activated or catalyst coated charcoal and a hydrophilic binder, the second activated or catalyst coated charcoal with a hydrophobic binder, the third layer carbon black and a hydrophobic binder. Pref. compsns. are: 1st layer 10-20 (15)% carbon black, 80-90 (85)% Pt or Pd charcoal, plus 10-50 (30)% polysulphone or polytrifluorochlorethylene; 2nd layer Pt or Pd charcoal/50% PTFE; 3rd layer carbon black/80% PTFE. A metal grid may be incorporated in the first layer. The electrodes give good liq./gas equilibrium and are wetted well by the electrolyte without flooding.
Appts. for mfe. of a clad tube for a lead accumulator, comprising rollers and a conveyor for transfering an oxidiation resistant fibrous mat, a mat winding core disposed at a predetermined angle to the conveyor and rollers or a propulsion mechanism for continuously removing a clad tube from the core. The speeds of the movable parts are respectively synchronized. Mat is e.g. of glass fibre.
Gas electrode comprises a porous base plate, a filmy material attached to a gas side of the electrode plate, and a layer of fluorine contained resin powder formed between the electrode plate and the filmy material, a part of the layer being contained in the filmy material.
Powdery rubber is added to a copolymer consisting of polyethylene and vinyl acetate to make a mixture. After a periphery of a cathode bottom plate is coated with the mixture, it is heated to make a coating. After the bottom plate is electrically attached to a bottom of a zinc can in which power generating elements are disposed, a lower end portion of a casing is bent inwards and compressed so as to be attached to the coating.
Method of fabricating a dry cell, comprises disposing a metal ring to a contacting porting of a sealing member and a coating formed on a zinc can surface, the sealing member and coating being made of heat melting synthetic resin, and inductively heating the metal ring to join the resins of the contacting portion with each other and simultaneously to form a resin layer by heat melting synthetic resin powder at the outside of the metal ring.
ZnMnO2 primary battery having a nickel-plated steel case also acting as a depolarising electrode collector, a compressed MnO2 annular depolarising electrode allied to an electroconductive material, within which is a zinc paste tube separated by a separator, and a negative electrode collector tube of perforated metal free from active material, abutting the internal face of the zinc paste tube, in which the element contains equivalent amounts of material which can be used electrochemically, and the separator consists of a finely perforated plastic tube acting both as a support and as a cylindrical separator open towards the cover, absorbent, resistant to alkalies and surrounding the plastic tube.
A fuel cell has a closed housing having a wall through which extend tubular inlets for fuel and oxidant to communicate with a molten alkali hydroxide electrolyte which is corrosive to metals and held at 400 degrees C. A tubular plug of high temperature, non-corroding plastics material, non-wetting to the electrolyte is interposed between the outer surface of each gas feed pipe and the inner surface of its inlet at a cooler location spaced from the housing wall. The fuel feed pipe is secured to a large cross section anode support extending above the electrolyte level.
Cotton linter, alkali treated to impart liquid retaining ability and swelling props., is mixed with 10 wt.% of natural or synthetic fibre, whose fibre length is greater than that of the cotton linter to increase its mechanical strength. Examples of fibre are vinylon, polypropylene, nylon.
A voltaic cell comprises (a) a lithium-aluminium alloy anode contg. 1-20 wt % lithium and having a reduction potential of 0.2V. less than lithium metal, (b) an electrolyte of neutral solvent, esp. N,N'-dimethylformamide contg. sufficient lithium hexafluorophosphate to give a conductivity of 0.001 ohm -1 cm. -1, esp. 15-24 wt %, and (c) a reversibly reducible metal cpd. or sulphur cathode depolariser. The depolariser may be mixed with carbon black and electrolyte to form a paste or with carbon black and PTFE to form a self supporting electrolyte permeable membrane.
A method of hardening an electrolyte for dry cells, comprises adding to an electrolyte a mixture composed of acrylamide or monomer to be polymerized with acrylamide, and hardening the mixed electrolyte by redox group catalyst, water soluble beta-diketone groups being employed as the reduction constituent of the redox group catalyst. As the oxide constituent of the redox group catalysts are employed persulphate such as ammonium persulphate, potassium persulphate, sodium persulphate, etc. are water soluble catalysts such as hydrogen peroxide. As the water soluble beta-diketone groups are used acetylacetone, benzoylacetone, benzoylmethane, malonedialdehyde, propionylacetone, butylylacetone, isobutylacetone, dipropionylmethane, hormylacetone.
This invention relates to casings suitable for fuel cells or batteries using alkaline electrolytes. Casing comprises an alkaline proof fibre formed on the inner wall of the casing, and a casing constituted by glass fibre and alkali proof synthetic resin, e.g. epoxy resin. As the alkali proof fibre, the fibres comprise nylon, vinylon, ethylene group, propylene group, fluorine group etc. The casing with long service life can be obtained since it is not eroded by the alkaline electrolyte.
Process comprises the preparation of a mixed liquid by mixing an additive, which consists of powdered carbon, diatomaceous earth, etc. in a microporous solid form or of fibrous substances, etc. with a soln. obtained by dissolving synthetic resin in a solvent or a synthetic resin latex soln; the charging of the outlet portion of the cell cover with the liquid to make the liquid dry, and the formation thereby of a gas permeable microporous layer integral with the cell cover material surrounding the outlet portion. Synthetic resins such as PVC are used with solvents such as methyl ethyl ketone. The synthetic resin latex soln. is one prepared by dispersing particles of synthetic resin such as polystyrene in water. Product has excellent appearance and is free from danger of leakage or explosion.
Mfe. of a sealed battery in which a mixture of powdered thermoplastic resin, with hydrated silica gel opt. contg. a catalyst, is arranged around a number of plates with porous separator layers between them and heated to &gt;100 degrees C in saturated steam to form a liquid absorbing body, which is subsequently impregnated with an electrolyte and placed in a can.    The terminals of the plates are connected in series and the can sealed by known methods. The cell of invention does not lose electrolyte through the case.
Fuel cell comprising a stack of disc shaped porous plastic (PTFE) electrodes coated with activated carbon (oxidant electrode) and tungsten carbide (fuel electrode) and arranged in pairs of similar polarity except for an anode and cathode at opposite ends. There are separate circuits for each fluid:- oxidant, fuel and electrolyte - arranged so that oxidant and fuel pass between electrodes of the same polarity whereas the electrolyte flows between electrodes of opposite polarity. Current is carried by graphitsised paper sintered within the electrodes, the pref. oxidants are oxygen or air, the fuel hydrogen or hydrogenated gases.
Each group of plates has a vertical lug placed against the appropriate divider wall in which there is a cut out through which the cell strap is placed and welded to the lugs. A split mould tool, e.g., of steel is placed in position on either side and molten thermoplastic material, esp., an EVA compound poured in whic when cool provides a liquid tight seal to the strap and to the edges of the cut out. The sheath so formed is flush with the top edge of the wall. The single piece lid of thermoplastic material is welded to ensure seal, tot he top edge of the walls, the dividers and the strap sheaths. Inter cell isolation is thus simply guaranteed.
A method for making a partition, consists of agitating an aq. solution of PTFE, then kneading it to produce a substance which is formed into a panel. Specifically, acid and/or alkali-resistant powder, or an ion exchange resin powder may be used as filler material. Used as a membrane in an electrolytic cell for concentrating sea-water, in resultant microporous structure offers considerable resistance to blocking of the pores due to plankton.
Two or more, esp., two layers of absorbent material are made into a lamintate, the inside face of one or both being coated with a gel froming material which after drying is microporous and has membrane properties which increase the cell life in terms of charge discharge cycles by preventing dendritic crystal growth esp., between a zinc based cathode and an oxide of nickel based anode.
A central anode current collector carries an active anode mass of consumable metal, esp., Zinc amalgam, mixed with an alkali hydroxide electrolyte in paste or gel form. This is surrounded by a cylindrical, tight fitting cathode of a nickel mesh current collector with an external water repellent porous membrane esp., of PTFE, and an inner electrocatalyst layer of e.g., silver esp., in powder form in a PTFE binder. An outer reinforcing tube of heat shrunk or elastic material prevents internal gas pressure from causing voids between the anode/electrolyte mass and the cathode and an outer perforated ventilation can encircles the whole, with end seals and electrode contacts.
Process comprises sticking a a base sheet on to a drum on which adhesive is previously coated, rotating the drum, stripping the base shet from the drum with a scraper situated at one side of the drum and winding the base sheet around a core to form a clad tube. Sheet is pref. of glass fibre, synthetic fibre or non woven fabric.
Electrode base made from carbon, graphite fibres, coke, carbon black, craft paper, or the like, and a binder (tar, pitch and/or phenolic resin) is heated to a temp. above 700 degrees C; then coated with an active layer (thickness &lt;10 mu) contg. ruthenium, oxygen and carbon (by preliminiary oxidation, followed by deposition of ruthemism or its salt, and heating at 300-900 degrees C). The specific resistance of the electrode is less than 0.01. OMEGA cm., the density is 1.00-2.20 g/cm3; and the short-time wearing is less than 0.3 mg/Ah. The chlorine overpotential is relatively low. The coating firmly adheres to the substrates.
Paste plates with lead strip reinforcement running circumferentially but not axially are wound with intermediate separators of short staple, absorbent glass fibre felt into a tight coil and sealed in an outer casing, with a leakproof, pressure relief valve fitted, breather, only sufficient electrolyte being included to maintain the plates and separator in a wetted condition. The plates are not inherently self supporting, the mechanical rigidity being provided by the tight fit of the coiled assembly in the case. Due to the low % of strengthening additives in the lead, the cell internal resistance is lowered and the capacity/weight ratic increased.
One or both of the outside layers of the sandwich are of non mesh, uniformly microporous material e.g. of one or more layers of homogeneous microporous filter paper esp. of cellulose with a degree of polymerisation 3500, and the central layer a semipermeable member are esp. of regenerated cellulose. Where one layer only of the first type is used it is placed against the zinc negative electrode and has an air permeability of 3-3048 cm3 per min. per sq. cm. The outer layer, against the nickel positive electrode, may be of non woven, coarse pored, material with low absorbency. The separator is impregnated with enough electrolyte only to wet uniformly the electrodes and is compressed in a tight roll between them before canning. Due to slow dendritic growth cell life is increased.
An anode of high purity esp. a min. 99.9% Al is placed within the cell, and a porous silver, esp. of sintered powder, cathode forms at least part of the wall of the cell housing. A membrane of either porous or non porous material may be applied to the inner or outer face of the cathode, e.g. a porous PTFE membrane with pore size of 1-10 mu on the outer face. A double ended or a multiple cell battery configuration can be used. reliable life is extended up to e.g. 5-10 years due to isolation of oxides from body tissue.
Opaque microporous membranes based on PVC have a porosity of 40-85% and contain micropores with a diameter below 0.1 mu.    As compartment separators in accumulators and fuel cells, and in ultrafiltrations for separating macromolecules according to their mol.wt. the mol. wt. limit for macromolecules which migrate and whose which do not migrate being 40,000-70,000. The those which do not migrate being 40,000-70,000. The membranes are free of solvent residues in their pores.
Accumulator, particularly a multicell lead accumulator, consisting of a casing fabricated from an elastic plastic material, e.g. polypropylene, has sloping ribs possessing spring energy are provided on the bottom and in the front and partition walls of the casing, between limiting ribs so that the plate assemblies can be fixed in the cells.
Dense graphite structures of particular use in acid fuel cells are made by mixing a phenolic binder and a vaporizable dispersant, blending powdered graphite into the mixture to form a slurry contng. 75-95 wt. % graphite, and 5-25 wt % of binder, drying the slurry to drive off the dispersant, and then pressing the mixture thus formed in a mould, first at 180-220 degrees F at 100 psi and then at 2500-3500 psi at 300 degrees-400 degrees F after the temp. during the first pressing rises to a given value.    Finally cooling is effected under the full pressure. The structure thus formed may then be post-cured at 325 degrees-400 degrees F if desired. Such a method affords the production of intricate high density shapes without the necessity of machining.
The external non-reacting surface of a dry cell Mg anode is covered by a protective coating of water impervious material to prevent loss or deterioration of electric contact with an adjacent battery cell. The thin coating consists of dense, inert material such as an epoxy primer.
A container for an electrolytic cell contg. separate anode and cathode solns., has a vessel inside the container, to hold one of these solns. The vessel is of ceramic material, one of its walls constituting the diaphragm between the soln., while the other walls and floor are faced with a gas-sealing layer. The arrangement permits heating and cooling of the electrolyte, e.g. to regulate anodising of an aluminium surface, without stressing the ceramic membrane. The gas sealing layer is pref. an external coating of PVC.
Water rewettable, pref. highly anisotropic membrane is made by impregnating the pores of a porous polysulphone membrane with the vapour of a lower alkanol (pref. MeOH) or methyl ethyl ketone, condensing the vapour onto the surface of the pores and opt. immersing the membrane in water. Used as moisture vapour transmission elements in e.g., fuel cells. It has high transfer rate and selectivity.
A tinned metal cup is attached to the base of a dry cell, in electrical contact with the negative electrode by a plastic ring, pref. polyethylene, which fits over the cup and is secured to a thermoplastic sheat encasing the cell, by friction welding.
Non aqueous electrolyte for Li anode cells comprising LiAlCl4 and NR4Cl where R = Me, Et, Pr, Bu pref. Et. dissolved in SOCl2. The concn. of LiAlCl4 plus up to 5 mol % NR4Cl is 1-2 mole/litre. The cathode is pref. sintered nickel and the separator polypropylene felt. The addition of NR4Cl neutralises any excess AlCl3 which otherwise attacks the Li anode. The electrolyte is prepared by adding AlCl3 then LiCl to SOCl2. Addition of NR4Cl may precipitate some LiCl which is filtered off.
A sealing compound for openings of a battery produced by blending rosin, stearic acid, and a liquid form styrene-butadiene rubber and opt. vulcanising agent with asphalt, pitch for a mixt. thereof.
Forming an unprocessed mat using for example, glass, polyester and polyacrylic fibres and stitching up the unprocessed mat at intervals with sewing threads so that linear grooves may be formed at the stitched portions.    The grooves formed on the mat surface at the stitched portions allows the diffusion of the electrolyte and gas, thereby improving the initial performance of the battery.
The non-porous, electrically conductive film comprises 20 - 40 wt.% EVA copolymer, up to 10 wt. % polyisobutylene, and the remainder Ag, Au, Cu, Al, Zn,graphite or carbon black. The film is less than 10 mils thick and has transverse resistivity &lt;5 ohm-cm and longitudinal resistivity pref. &lt; 2 ohm-cm. It is used as an inter cell connector in a LeClanche-type battery.
A polyolefin (esp. polypropylene or polyethylene) container and its cover can be sealed by sulphonating them to the extent of at least 0.005 mg sulphonate gps. per sq. cm.; applying epoxy resin to the locus of the seal, assembling the cover and case and curing the assembly.
A high output voltage bonded battery electrode is prepared by successively coating a metal support with (A) conductive metal (pref. noble), carbon or graphite particles and (B) lead dioxide particles, in uncured thermosetting resin, and curing the resin separately or simultaneously. There is enough lead dioxide to react with the electrolyte and enough conductor to provide a conductive path through the first layer and prevent an interfacial resistance barrier between the support and active material.
Voltaic cell comprises two half cells separated by a separator permeable to hydrogen ions and water the cathodic half all contng. a halogenate as depolariser and the anodic half cell contng. phosphorus together with a reagent for changing the phosphorus to phosphoric acid. The latter reagent is pref. I and the halogenate is KClO3, KBrO3, NaIO3, Ca(IO3)2 or Mg(IO3)2. The electrodes are of carbon, and the electrolyte is H2SO4, HClO4 or H3PO4.
Electrochemical cell has an anode space contg. a redox couple based on at least one of the metals Bi, Pb, Te, Se, Co, Ni, Fe, Th, Sb, Cu, Hg or Ag) and uses a fuel consisting of formaldehyde, polymerised formaldehyde and/or formate ions. The electrolyte in the cell has a pH of at least 8, when the fuel is formaldehyde and has a pH of 3-7 when the fuel is formate. The cell gives a constant electric current for a long period practically without loss of the components of the redox couple, as long as oxidisable fuel is present.
A galvanic battery of the alkaline type in a flat design is enclosed between two plastic foils (PVC or polyethylene) one of which has been made conductive by an addition of carbon or titanium powder. The insulated foil has a central hole, sealed at the rim by a compound through which a tin foil makes contact with a zinc electrode. This electrode is divided by a separator from the depolarizer (carbon, MnO2 and electrolyte.)
Electrode, consisting of porous top coating on fibrous material and layer of catalyst powder, has butadiene-styrene-acrylonitrile (ABS) copolymer as binder for catalyst layer and top coating and also between these layers. This electrode is used in electrochemical cells, esp. bipolar or Janus electrodes and fuel cell batteries. Bonding between catalyst particles and of these and top coating is improved.
Paralleledpiped reinforced plastic container for electric accumulators is made from a light transparent plastic material, and has a reinforcing frame applied to at least two vertical walls of the container. Pref. the container is made of an acrylonitrile copolymer e.g. styrene-acrylonitrile copolymer. The container is as transparent as a glass container, is resistant to sulphuric acid, is light and easily moulded, and has a good resistance to impacts and extreme temps. The frame maintains the dimensional stability of the container. The frame has at least two pieces in the form of an arc whose convex part is supported on a large vertical wall of the container. These pieces are provided with a metallic or reinforced metal cord between the arcs, and are connected and placed under tension by braces.
A wafer type electrode unit is provided for high capacity alkaline batteries, for aircraft, or e.g. portable tools or X-ray units, record players, television and radio equipment or engine starters. The zinc electrode particularly, or also the silver, cadmium, or nickel electrode, is about 0.010-0.150 inch thick and supported on opposite sides by porous plates of sintered inorganic material, pref. 0,010-0,030 inches thick. The margins of the plates extend beyond the electrode and the space between them is filled with materail bonded to the plates. The preferred filler is epoxy resin, or may be polyvinly, neoprene, or ethylene propylene rubber. Plates are e.g. of alumina, aluminosilicates, mixtures of metal oxides and the like. Silver electrodes may be left un-unitized and interleaved with unitized zinc electrodes. No additional sealing is needed and the electrodes are firmly supported.
Flexible porous separators suitable for use in high energy density batteries using alkaline electrolytes and operating at up to 100 degrees C. The separators are made of 50-95% inorganic material and 2-35% of potassium titanate fibres, the whole bound together with 2-45% of a compsn. comprising a curable organic polymer and as a second component 5-50% (based on total organic components) of monomeric or polymeric azelate, pelargonate or oleate ester. The separator has porosity of 5-40%, pore size 1-400 A and thickness of 0.001-0.025 inch. The separator, which is very flexible and has very low resistivity (about 5 ohm-cm) may be used in various battery configurations, and may be formed on or impregnated in various support materials such as flexible potassium titanate, asbestos and nylon, or adhered to the electrode surfaces. The pref. curable polymer is polyphenylene oxide and the polymeric esters have av. mol. wt. 800-10000 (pref. polypropylene polyazelate of av. mol. wt. 2000-6000). The pref. inorganic material is chosen from solid soln. of Mg silicate and Zn or Fe silicate, zirconia, solid soln. of MgO and zirconium dioxide and chromic oxide, and solid soln. of ferrochromite.
Matrix (I) for a flexible fuel cell separator is of low electrical resistivity and high stability to alkalis at high temps. over an extended period is made from a chrysotile asbestos mat which is uniformly impregnated with polyphenylene oxide (0.5 to 25% by wt).
Battery electrode is made by contacting sponge-like organic material (I) with slurry contg sinterable inorganic material (II) including a metallic constituent (III) and plastic binder (IV) which decomposes at a higher temp. than (I). (IV) is dissolved in a solvent, (I) is heated to 200-400 degrees C causing decomposition and removal of (I), followed by heating between 400 and 600 degrees C which causes sintering of (II) and further decomposition and removal of (IV). Further heating and sintering of (II) is effected at 750-950 degrees C giving a strong porous matrix of (II). (IV) is stable to the initial sintering while (II) is self-supporting once (IV) is decomposed and removed. Battery can be used for power generation in airborne systems.
These electrodes contain mixed or alloyed non-stoichiometric carbides of at least two metals selected from Ni, Co Fe and Mn, applied onto an electronically conducting framework, e.g. by spraying a suspension of finely ground components in a volatile liquid, and sintering in vacuum or an inert atmosphere. A porous hydrophobic layer (pref. PTFE or a hydrocarbon polymer) is applied onto the gas side of the electrode. These electrodes have high catalytic activity and are resistant to attack by alkaline electrolytes. They are relatively inexpensive.
Process comprises adding to the electrolyte of a dry cell, a polymerisable substance consisting of acrylamide or a mixture with a monomer that can copolymerise with acrylamide, and then polymerising and hardening the monomer using a redox-type catalyst using as reducing compounds one or more compounds of general formula: R1R2-C(Y)-C(=O)-C(X)-R3R4 (where X denotes OH or COO-Z (Z represents H, K or Na or is not &gt;3C alkyl radical Y is H or OH, acryloyl or methacryloyl radical; and R1, R2, R3 and R4 denote H, or is not &gt;3C alkyl radical provided that if X is COO-Z, either one of R3 and R4 must be H).
An absorbent separator for an electric battery comprises an elastomeric resin binder (I) forming a continuous matrix blended with a gelling agent (II) capable of absorbing and retaining battery electrolyte, (I) comprising 10-30 wt. % of the separator (the rest being II), at least 50 wt. % of (I) being a vinyl acetate-ethylene copolymer, and (I) and (II) being blended in such a way that (II) is not gelled until it contacts the electrolyte. The absorbent separator prevents corrosion during high temp. storage by keeping the anode surface uniformly wetted with electrolyte. (II) may be starch, flour, carboxymethyl cellulose, methyl cellulose, polyacrylamide resins, gums, or silica gel.
The sieved gas-activated carbon is mixed with one or more binders, applied to a metal mesh and sintered, followed by rolling or pressing. Catalyst is incorporated before sintering or after rolling or pressing.    The catalyst is pref. Raney nickel, nickel boride or a metal or mixture of metals in sub-groups VIII. The binder is pref. a hydrocarbon polymer e.g. low-pressure polyethylene or other high polymer e.g. Miramid (RTM).    The electrodes are cheaper than known types and have very high durability under intermittent loads.
A fuel cell is set up which uses the amino acids (40 mg/l alanine and 18 mg/l glycine) present in the blood as fuel, their anodic oxidn. being catalysed by a redox system, pref. of isatin (deriv.), acenaphthequinone or pyridoxal (phosphate). The catalyst contains at least one alpha-diketo gp. and the blood is also used as O2-source. Long life cells are obtd. which are suitable as heart pace-makers.
The enclosed lead storage battery has a double layer element mounted on the boundary between vapours in the storge battery and open air. The double layer element comprises a high water proofed non-catalytic outer layer and an element impregnated with electrolyte is mounted on the inner layer, one portion of the element being soaked in electrolyte. An auxiliary electrode is connected via an external resistance to the positive electrode, and is situated in contact with the electrolyte in close proximity to the double layer. This forms a secondary cell for the prodn. of water within the enclosed lead battery.
D.C. source consists of a no. of fuel cells connected in series, each with a (quais)solid electrolyte and electrode, the first exposed to a gaseous fuel and the second to a gaseous oxidant. The solid electrolyte consists of two half-tubes, joined gas-tight to a tube. The first electrodes are on the inside and the second electrodes on the outside along a helix and there is electrical contact between the first and second electrodes or adjacent fuel cells at the contact surface of the half-tubes. This simple construction overcomes the difficulties of obtg a gas-tight seal in a series of high-temp fuel cells.
A compatible O2-free fluid (pref. N2 etc.) is supplied to the oxidant space of each cell in a cell system whilst H2 is being supplied to the fuel space during cell start-up or shut-down.
Electrolytic cell having at least one separator, between the anode and cathode, which consists of a polymer soln. which has been directly deposited on a first electrode, forming a solid "skin" aftery drying and which is swellable in contact with the electrolyte; and a second electrode directly applied onto the surface of the separator coating in form of a suspension of granular active material in the electrolyte.
Battery consists of a number of electrochemical cells in parallel, providing an electrolyte supply to them through common main inlet and outlet channels. To ensure the same operational pressure difference across all cells, the cross-sectional area of the main outlet channel is made greater than that of the main inlet channel, and the section of the latter can be designed to become progressively smaller in the direction away from the inlet while that of the former is made gradually larger towards the outlet.
To achieve adequate humidification of the air which is fed via a soda line scrubber to an electrochemical cell including an alkaline electrolyte (e.g. a fuel cell including KOH soln.), a constant proportion (e.g. 5% by vol.) of the total flow rate of the output air from the cell is recirculated to the air input of the scrubber. This humidification (e.g. so that the inlet water vapour pressure is about 15 mm Hg) is sufficient to prevent the electrolyte drying out.
In the removal of CO2 from mixts. with H2 e.g. in reformer gas, for use in alkaline hydrogen-oxygen fuel cells, by means of bi-porous absorption and desorption units in a cycle through which the gas and washing fluid pass, the difference in av. hydrostatic pressure in the absorber fluid and av. electrolyte pressure in the fuel cell is controlled at a fixed value. The pressure difference is pref. controlled so that the gas pressure in the absorber is sufficient to keep the coarse pores free of fluid but not the fine pores.    Safe operation of a combined gas washer-fuel cell system is obtd. with a minimum of control elements.
A hydrogen fuel cell system consists of a fuel cell and a hydrolysis cell. The former has electrodes of porous C plates and counter-electrodes of porous tungsten carbide plates. The hydrolysis cell connected a control valve has in a bath of diluted H2SO4 a set of N2-foils which are connected by bus-bars to a d.c. source.
Electrodes consist of a carrier of a film-forming metal or alloy (esp. Ti) with a coating comprising (a) is not &lt;1% RuO2 (b) is not &gt;50% TiO2 and (c) 1-80% of one of more of SnO2, GeO2 and oxides of Sb, such that the wt. ratio (a):(b) is &lt;2:1. The coatings are applied by coating the carrier with a solution of heat-decomposable compounds of Ru, Ti and Sn, Ge or Sb in an org. solvent, drying off the solvent and heating the electrode in an oxidising atmosphere at &gt;350 degrees C. Specif. claimed coating consists of 20-50% RuO2, 40-50% TiO2 and 5-25 wt.% SnO2. The electrodes are esp. useful for alkali metal chloride electrolysis where it has low over-potential and for cathodic protection and fuel cells.
Primary element for controlling MeOH concn. in the electrolytes of MeOH-galvanic fuel cells has a cell transversed by electrolyte, fitted with anode and cathode and an automatic control system influenced by the voltage of this cell. The anode consists of a metal catalysing anodic MeOH oxidn., with O2-separation, while forming an oxide in the electrolyte. Reversible potential of formation of oxide is 20-400 mv below the O2-separation potential, and esp., between the reversible O2-potential and the O2-separation potential. For alkaline electrolytes, primary element anode consists of Ni and cathode is a Raney-Ni double skeleton catalyst electrode; for acid electrolytes, anode consists of or contains Pb. Anode is smaller than cathode. Anode and cathode may form a coaxial structure, esp., with cathode forming a steel cylinder enclosing a central anode wire.
Membrane, or tube, diffusion permeable by H2, for separation of H2 from gaseous mixtures as in fuel cells or in the prepn. of heavy water, comprises an imperforate substrate of Fe, V, Ta, Ni, Nb or an alloy of these with a discontinuous and/or porous Pd (e.g. 99% pure) or Pd alloy (e.g. contg. 10-40% Ag) film on each side. The coating may be applied by printing, spraying or electrodeposition and the product may pref. be 0.0005-0.0016" thick, and may be made from a thicker coated product by rolling.
The porous plate, pref. of Ni with 35-80% porosity, and its porous projections, allows the electrolyte to circulate and still maintain constant contact with the anode. The purpose is to provide a constant amount of electrolyte in contact with the electrode to ensure a constant electrical output, and also give a built-in cooling effect on the electrolyte. Electrodes pref. comprise light webs which lie in a catalyst compsn. contg. a hydrophobic polymeric binder, pref. PTFE.
A partial oxidation reactor of hydrocarbons for producing a product stream for fuel cells has a central tube into one end of which a feed stream is injected to emerge from the other end and flow in reverse direction through the annulus between the central tube and an intermediate tube. Some of the stream then recirculates back into the upstream end of the central tube but the remainder again reverses direction and flow through the annulus between the intermediate tube and an outer tube to an outlet. The product stream contains no free carbon.
Bibulous polymeric material, suitable for use as a battery separator in acid or alkaline batteries such as AgO-Zn comprises a copolymer of (I) methacrylic acid or mixt. of methacrylic acid plus 20% wt. of hydrophilic monomer contg. single unsatn. and (II) a crosslinking monomer contg. 2 polymerisable unsatns. or (III) a hydrophobic monomer contg. single unsatn. or (IV) a mixt. of II and III. The polymeric material has a porosity &gt;50%, pore diam. &lt;300 angstroms and a vol. resistivity &lt;20 ohm cm. The wt. ratios of the components are I : II is 125-8 : 1; I : III is 3-1.5 : 1; I : IV is 5-2.5 : 1 and ratio of II : III in IV is 5-1.5 : 1.
Covers for cells with acid electrolytes are produced by (a) dressing amphibole, esp. anthophillite, asbestos with a cationic wetting agent until the fibre bundles have disintegrated, (b) removing undisintegrated particles, (c) preparing a uniform suspension of asbestos fibres and fillers in the form of powder with particle size is not &gt;100 mu. which are stable in acid electrolytes, can conductions and can swell to several times their vol., and (d) treating this suspension with acid-resistant latex and making into a cover in the usual way. These covers are capable of lasting function in acid medium. Latex is based on hydrophilic (saponified) butadiene-styrene-acrylonitrile copolymer, whilst fillter may be bentonite (20-50 wt.%) or cation exchanger (30-50%).
Cell producing electricity and soil-enriching agent byproducts has an anode comprising an electrode surrounded at least partially by particulate fossil fuel capable of forming alkali-soluble products, and O2-electrode cathode and an HNO3 electrolyte.
Fuel cell consists of (I) a fuel cell electrode, (II) an electrode with an oxidising agent, and (III) a molten electrolyte consisting of bismuth oxide (Bi2O3) or one of its eutectics, this electrolyte being in contact with I and II. The addition of CO2 to the air is unnecessary. The electrolyte operates effectively without any deterioration in the presence of impure fuels e.g. hydrocarbons. The polarisation activity is low.
A fuel cell which operates on air and impure fuel at relatively low temps. (120-300 degrees C) consists of a fuel electrode, an electrode with an oxidising agent, and in contact with both electrodes, a molten electrolyte contg. Tl2O or a eutectic thereof. The Tl2O may be supported on a porous carrier and/or be in a formed matrix contg. 15% of an inert solid material, pref. B2O3 or CeO2.
The anode is made into woven or sponge form, and placed in the path of the electrolyte contg. zinc particles such that the zinc particles are attached to the anode and that the residual zinc particles are exhausted outside the cell.
Insulating devices provided in the circulation system of a fuel cell using aq. alkaline electrolyte, each have means for dividing the electrolyte flow into fine drops in the upper portion of the container and, attached to the interior walls of the container is an alkaline soln.-repellent, e.g. wax chiefly composed of polyethylene resin of low mol. wt. The device enables the electrolyte concn. to be measured very accurately, simply and continuously, esp. in cases where many cells are used in series, if the electrolyte inlet or outlet of each cell is provided with the insulating device, the insulation between the cells is completed.
Phenolic resin fibres are coated with ground additional phenolic resin; formed into an electrolyte matrix; the additional phenolic resin is hardened; the matrix is filled with an acid and heated, to effect oxidation of the fibre surface, and thus to render them wettable. Uniform distribution of the electrolyte is achieved because of the improved flow conditions.
The amt. of catalyst of gas electrode in the element-cells below centre, in which temp. rise is high, is more than that in element-cells adjacent the electrolyte inlet. This ensures an even temp. distribution.
Oxygen gas is blown through a porous sintered Ni plate which acts as gas distributor and a +ve electrode, onto a fluidised bed of carbon powder at &gt;400 degrees C, a -ve electrode being placed in the carbon bed. The surface of the carbon is oxidised to CO2 and residual carbon is negatively charged this charge being collected by the -ve electrode and forming a current between this electrode and the +ve electrode in an external circuit. The blown oxygen also forms -ve charge via O2- ions by catalytic action of the Ni.
Cell comprises an oxidation electrode of sintered nickel contg. Ag catalyst, a fuel electrode of sintered nickel contg. Pt catalyst, an electrolyte of 30% caustic potash contg. 5% hydrazine fuel, an oxygen chamber, and an electrolytic cell. A separator composed of porous sintered nickel plate contg. Pt catalyst and an ion permeable film of, polyvinyl-alcohol, diposed on the fuel electrode side of the porous plate is arranged between the fuel electrode and oxidation electrode.
A fuel cell contains an alkali-metal hydroxide electrolyte, between cathode and anode, which is maintained above 300 degrees C in operation to render it molten and anhydrous. It is in contact with an O2-contg. atmosphere giving an alkali-metal peroxide or superoxide that acts as the sole fuel cell electrochemical oxidant. A barrier is combined with the cathode which impedes the transfer of electrolyte agitation, induced in operation to promote oxidant supply, towards the anode. A H2-containing fuel is also supplied to the cell.
The system comprise a fuel cell having a liquid body of liquid aqueous electrolyte in which hydrogen and an oxidant gas are reacted to produce electricity and water of reaction. Hydrogen gas is generated in a zone where water is reacted with a material which reacts with the water to yield hydrogen gas, which is then supplied to the fuel cell. The water generated in the fuel cell during operation is supplied to the zone where the hydrogen gas is generated. Pref. the reactive material is Si or Al and aq. soln. of a base is used to produce on reaction, an Al silicate insoluble in the medium.
A multiple fuel cell has stacked cells, each including in sequence a cathode, molten electrolyte, an anode and cathode on opposite sides of a gas impervious conductive support, molten electrolyte and an anode. A thin H2-permeable layer is on the anode support facing the adjacent electrolyte. Oxidant is supplied to the cathode and H2 fuel to porous anode support which also has a reforming catalyst supplied internally to it through vents, and which with the electrolyte at 400 degrees C, provides H2 that diffuses through it. Gas flows paths in the anode support bridge the vent and fuel introduction point.
In the compact structure of fuel cells disclosed in the Parent Patent in which bipolar electrodes formed from porous sheet and separated by semipermeable membranes, have elongated projection on each face which are sufficiently close to each other and are elongated in different directions from one electrode to the next so that any risk of telescoping of the electrodes and damaging the membrane is eliminated, the system of electrodes being constituted by several elementary rows of rectilinear segments each occupying a strip parallel to the edge of the electrode between which the electrolyte flows, two successive grids being symmetrical with respect to a straight line parallel to the edges of the electrode between which the flow takes place, the improvement whereby the rows of rectilinear segments make an angle of more than 15 degrees and less than 30 degrees with the overall direction of flow of the electrolyte from one edge of the electrode to the other.
A foaming agent is added to an electrolyte in a fuel cell and the electrodes are positioned mainly, and pref. entirely within the foam layer produced by agitating the electrolyte. The cell is conventional, with fuel and oxidant supplied to anode and cathode in separate compartments. At least the fuel, and pref. both reactants are contained in the foam. The foam promotes the electrochemical reaction, improving performance. Fuel and oxidant are pref. gases, which saturate the walls of the bubbles which break and run down over the electrode, supplying fresh reactants.
The cell is built up of oxygen electrodes, pref. fuel electrodes, which are not curved and are either parallel or in a polygonal assembly. They are arranged singly or in pairs in a plastic frame, esp. moulded on in a single operation.    High power/weight ratio, cheap and well sealed.
Metal oxide films (e.g. for high temp. fuel cells) are deposited in thin coherent from by (a) passing a carrier gas over a heated volatile chloride of the metal and (b) passing the carrier/chloride vapour over the heated substrate in the presence of water. The chloride is hydrolysed by the water to deposit oxide on the substrate. Mixed oxide films may be formed using 2 chlorides.
Recharg eable fuel cell comprises separate H2/O2 fuel cells and electrolysis cells, both containing hydrogen electrodes, oxygen electrodes, electrolyte and a water storage region either at the hydrogen or oxygen electrodes. The oxygen electrodes are connected via an oxygen storage region and the hydrogen electrode via hydrogen storage thus the reactive gases are readily transferred. Discharge of the fuel cell causes dilution of electrolyte which expands into the water storage matrix. The equilibrium water vapour pressure increases and water is transferred to the electrolyte of the electrolysis cell. A similar transfer occurs when electrolysis to regenerate H2 and O2 increases the electrolyte concentration. The use of separate cells permits optimisation of materials and operation mode, the transfer of gases and water requires no moving parts and the whole system can be hermetically sealed.
In mfr. of a thermally stable, crack resistant porous matrix for holding a fuel cell electrolyte, a minor part of liq. phase sintering agent is mixed with a major part of particulate ceramic oxide and a minor part of inorganic phosphate, borate, silicate or aluminate binder. The binder is activated and the mixt. heated to above the m.pt of the sintering agent to sinter the ceramic oxide particles. Pref. a mixture for use in a fuel cell having liq. carbonate electrolyte, contains 90-94 pts wt. magnesium oxide, 2-5 pts wt. alkali metal phosphate and 2-5 pts wt. lithium chloride, bromide, iodide, fluoride, carbonate or sulphate as sintering agent.
An aq. soln. of hydrazine is supplied as fuel to the interface between the anode and an aq. electrolyte in a fuel cell, and an oxidising agent is supplied to the cathode-electrolyte interface.    The anode and cathode are ionically connected, pref. by a selective ion-permeable membrane. Electric current is produced when the electrodes are connected through an electric load. In pref. embodiment, the hydrazine is in an aq. alkali hydroxide soln., and the oxidising agent is an aq. soln. of NHO3, H2O2, a perchlorate or a permanganate.
A battery of electrochemical cells, esp. fuel cells, with gas diffusion electrodes for operating with gases contng. inert gases has the gas spaces of similar electrodes of like polarity connected in parallel within the individual groups, while the groups are connected in series on the gas side; the number of gas spaces in successive groups continuously decreases. The advantage of the arrangement is a reduction in inefficiency caused by scatter in the gas flow resistance values of individual electrodes.
A fuel cell power plant has a halogen generator comprising a steam reforming reactor in which steam is reacted with gaseous hydrocarbon fuel to produce at least molecular hydrogen which is supplied to the fuel cell anode. The feedstock supplied to the reactor is desulphurized by an arrangement upstream thereof. The effluent from the anode is fed back to an ejector, upstream of the desulphurizer, where it is mixed at least into the steam portion of the feedstock to promore hydrodesulphurization.
A fuel cell is one in which the air electrode comprises two porous layers having different porosity, the layer situated nearest the electrolyte having finer pores than the layer situated nearest the atmosphere. In addition, the electrolyte chamber forming the fuel cell is connected via a valve to an evacuated chamber maintained below atmospheric pressure by a pump which is generated intermittently by electric energy generated in the fuel cell. Further the electrolyte storage vessel in the electrolyte circuit is arranged to have a volume large in relation to that of the electrolyte chamber of the fuel cell. If the fuel is gaseous instead of being dissolved in the electrolyte, the fuel electrode also comprises two porous layers having different porosity.
Fuel cel contg. a liquid fuel e.g. methanol, ethanol and formalin and electrolyte of metal salts contg. CO32-ion (e.g. K2CO3), is characterised in that the fuel electrode comprises a powdered stainless steel, a powdered carbon, a resin binding agent and a catalyst. The fuel electrode has durability, resistance against electrolyte contg. CO3-- ion, and improved mechanical strength.
A device for simultaneous circulation of a liquid and a gas and regulation of the gas pressure, consists of a rigid vessel divided into two compartments by a flexible membrane, impermeable to gas and liquid, the first compartment being joined to liquid entry and exit ducts, each provided with a non-return valve, a spring acting on the membrane to increase the volume of the first compartment, the second compartment being joined by gas entry and exit ducts, the entry duct being associated with a spring operated valve arranged so that when the volume of the first compartment increases the membrane pushes the valve spring so as to permit entry of gas. The device ensures good circulation of electrolyte and a controlled gas upply pressure to a fuel cell. The non-return valves consist of diaphragms of elastomer, pref. neoprene, inserted between orifices in a series of plates. The spring acting on the membrane may be a corrugated sheet.
Fuel cell has a cavity within the cell casing contg. H2-producing cpd. (e.g. metal hydride) exposed to the anode, such that water vapour may combine with the cpd. to generate H2 which is then diffused to the anode and consumed. Operational control is maintained by a wick connected to an external reservoir and to the casing interior such that water is drawn into the wick as the pressure inside the cell drops. This allows increased water vapour diffusion into the H2-producing cavity thus generating more H2.
A fuel cell has a closed housing having a wall through which extend tubular inlets for fuel and oxidant to communicate with a molten alkali hydroxide electrolyte which is corrosive to metals and held at 400 degrees C. A tubular plug of high temperature, non-corroding plastics material, non-wetting to the electrolyte is interposed between the outer surface of each gas feed pipe and the inner surface of its inlet at a cooler location spaced from the housing wall. The fuel feed pipe is secured to a large cross section anode support extending above the electrolyte level.
Corrosion - resistant inert fine-porous matrix comprises free flowing particles of ThO2, ZrO2, CeO2 or Al2O3, or admixtures of these with silica. Partic. useful in high-temp. fuel cells. The powders may be opt. moulded and sintered into porous structures.
A movable fuel cell using oxygen and air as anode oxidizing agent, hydrazine sulphate as cathode reducing agent and a metal such as iron, aluminium, etc. to decompose the hydrazine sulphate to generate hydrogen which is supplied to the cell.
This invention relates to casings suitable for fuel cells or batteries using alkaline electrolytes. Casing comprises an alkaline proof fibre formed on the inner wall of the casing, and a casing constituted by glass fibre and alkali proof synthetic resin, e.g. epoxy resin. As the alkali proof fibre, the fibres comprise nylon, vinylon, ethylene group, propylene group, fluorine group etc. The casing with long service life can be obtained since it is not eroded by the alkaline electrolyte.
Fuel cell employing liquid hydrocarbon gas as fuel, utilises waste gases by operating a cooler with the liquid hydrocarbon gas, introducing the hydrocarbon gas in a fuel cell as cathode fuel, mixing exhausted hydrocarbon gas with exhausted gas at anode such as CO2, O2, N2 and adding the mixed gases to main fuel gas.
Cell has a transparent wall, and O2 supplied to inlet is ionised at surface of Ni electrode and oxidises Cu2O to CuO at surface of an ion exchange resin plate. When Cu2O is expended it is regenerated by solar irradiation through transparent wall.
High temp. cathode of C and Ni powder is heated by outflow of gas, and is separated by permeable wall from low temp. anode of Cu cooled by water. CO produced in high temp. zone enters low temp. zone and is oxidised by Ni powder and is vented from cell.
Fuel cell comprising a stack of disc shaped porous plastic (PTFE) electrodes coated with activated carbon (oxidant electrode) and tungsten carbide (fuel electrode) and arranged in pairs of similar polarity except for an anode and cathode at opposite ends. There are separate circuits for each fluid:- oxidant, fuel and electrolyte - arranged so that oxidant and fuel pass between electrodes of the same polarity whereas the electrolyte flows between electrodes of opposite polarity. Current is carried by graphitsised paper sintered within the electrodes, the pref. oxidants are oxygen or air, the fuel hydrogen or hydrogenated gases.
Reformer has reactor-burner assembly consisting of a housing with combustion products outlet, in which a cylindrical reactor canister is fitted. Canister has reactant inlet and product outlet and has catalyst bed packing for converting hydrocarbon/water feedstocks to H2 and C oxides product. An ejector inlet directs fuel, e.g., anode effluent, and air mixture into burner cavity at an angle, so that gas flows helically upwards in cavity. A burner insert is provided in lower part of housing, against inner surface, and has lower cylindrical section and inwardly conically tapering upper section to choke combustion gas flow. Heat transfer fins are mounted on canister and are within conical zone of insert, to absorb heat and block radiation towards upper part of cavity, thus maintaining prereactor chamber at suitable lower temp.
Dense graphite structures of particular use in acid fuel cells are made by mixing a phenolic binder and a vaporizable dispersant, blending powdered graphite into the mixture to form a slurry contng. 75-95 wt. % graphite, and 5-25 wt % of binder, drying the slurry to drive off the dispersant, and then pressing the mixture thus formed in a mould, first at 180-220 degrees F at 100 psi and then at 2500-3500 psi at 300 degrees-400 degrees F after the temp. during the first pressing rises to a given value.    Finally cooling is effected under the full pressure. The structure thus formed may then be post-cured at 325 degrees-400 degrees F if desired. Such a method affords the production of intricate high density shapes without the necessity of machining.
Water rewettable, pref. highly anisotropic membrane is made by impregnating the pores of a porous polysulphone membrane with the vapour of a lower alkanol (pref. MeOH) or methyl ethyl ketone, condensing the vapour onto the surface of the pores and opt. immersing the membrane in water. Used as moisture vapour transmission elements in e.g., fuel cells. It has high transfer rate and selectivity.
Regeneration of appts. with porous Ni equipment comprises circulating ammoniacal soln., which takes up Ni oxy-cpds., through appts. with at least periodic penetration into porous Ni part.    Technique is economical and simple.
Electrochemical cell has an anode space contg. a redox couple based on at least one of the metals Bi, Pb, Te, Se, Co, Ni, Fe, Th, Sb, Cu, Hg or Ag) and uses a fuel consisting of formaldehyde, polymerised formaldehyde and/or formate ions. The electrolyte in the cell has a pH of at least 8, when the fuel is formaldehyde and has a pH of 3-7 when the fuel is formate. The cell gives a constant electric current for a long period practically without loss of the components of the redox couple, as long as oxidisable fuel is present.
Composite electrode/solid electrolyte assembly for high temp. fuel cells in which the coarse pored substrate is coated first with a thin film of conductive, fine pored material over which the sealing coat of solid electrolyte is deposited in turn. Selective, localized pore filling followed by final removal of the pore filling material is used in mfr. The improved bond between electrolyte and electrode does not impair the ability of the reaction products to diffuse form the electrode.
A gas depolarised cell includes a vent to allow the gas pressures interior and exterior of the cell to equalise the vent comprising an aperture of volume closed by electrolyte-phobic material.
Matrix (I) for a flexible fuel cell separator is of low electrical resistivity and high stability to alkalis at high temps. over an extended period is made from a chrysotile asbestos mat which is uniformly impregnated with polyphenylene oxide (0.5 to 25% by wt).
An electrical generator comprises catalytic reformation of hydrocarbons or methanol, amine extraction of CO and CO2 from the reformed gases and from air, elimination of residual traces of CO, CO2 by catalytic methanation and a hydrogen/air fuel cell using alkaline electrolyte and not requiring platinum catalysts.
The pump which is driven by gas or vapour and has diaphragms instead of pistons is controlled by mechanically operated three-way valves operated by snap-action mechanisms each including a leaf spring which is actuated by a piston rod of the pump via a switch rod and a pressure pin even at low piston speeds. Infinitely variable control which is required when metering fluid fuel in a fuel cell is possible.