TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Components: The fluid management system controls both moisture and temperature conditions inside the housing. The fluid management system comprises one or more air holes in a wall of the housing, and an air-permeable, moisture-impermeable layer on or closely adjacent the biocathode for retaining moisture inside the housing adjacent the biocathode. The layer is positioned on or closely adjacent the biocathode between the biocathode and the wall of the housing. The layer is spaced no more than 100 mils from the biocathode. The housing comprises two parts adapted to be secured together to form the housing, and the fluid management system comprises at least one air hole but no more than two air holes in the housing for each biocathode. The air holes have a total air flow area which is at least 0.2% of electrode area. The venting system comprises tubing in the fuel reservoir having at least one vent port in the manifold, where the tubing comprises a tubing side wall defining an interior space, the tubing being of a material which is impermeable to the fuel but permeable to carbon dioxide gas, which is able to enter through the tubing side wall into the interior space and to exit the manifold via the at least one vent port. The controller is configured for controlling the output of the biofuel cell device according to a defined operating mode, where the controller comprises a switching circuit situated between the anode cathode assembly and a load, the switching circuit is responsive to the controller for alternately connecting the output of electrical current to the load and disconnecting the output of electrical current from the load according to the operating mode. The switching circuit comprises many MOSFETs. (I) further comprises: a power switch for manually selecting either an active state or an inactive state of the biofuel cell device, where the: power switch containing a magnet; and a Hall Effect sensor responsive to the magnet contained in the power switch for setting the biofuel cell device to the selected active state or selected inactive state; and controller configured for controlling the output of electrical current according to a defined operating mode when the biofuel cell device is in the active state. The fuel cell comprises a many fuel cells electrically connected in series. The operating mode comprises: alternately connecting one or more of the fuel cells to the load and disconnecting one or more of the other fuel cells from the load at a predetermined duty cycle; alternately disconnecting all of the fuel cells from the load and connecting all of the fuel cells to the load in unison at the predetermined duty cycle; and alternately disconnecting one of the fuel cells from the load while connecting the other fuel cells to the load. The predetermined duty cycle comprises 25% or 10% at 1000 Hz. (I) further comprises a converter circuit for regulating the output of the fuel cell before supplying the electrical output to the load. The controller comprises a supplemental power circuit for selectively connecting a battery to the output of the fuel cell for supplementing the electrical output supplied to the load by the biofuel cell device. The battery comprises a rechargeable lithium-ion polymer battery. The electrical output of the fuel cell is disconnected from the load and connected to the battery for recharging the battery. The controller comprises the MOSFET switching circuit. The biofuel coin cell device further comprises: a reservoir body defining the at least one reservoir, where the reservoir body having a first end face facing the cathode terminal and a second end face facing the anode terminal, at least one reservoir extending through the reservoir body from the first end face to the second end face, and at least one anode-cathode assembly being disposed on the first end face of the reservoir body with the assembly in contact with the fuel in the reservoir; a reservoir cap (821) having an end wall and a circumferential or annular side wall extending from the end wall to define a cavity for receiving the reservoir body (805), and a sealing member inside the cavity between the end wall of the reservoir cap and the second end face of the reservoir body for sealing the at least one reservoir; and registration means for aligning the reservoir body relative to the reservoir cap; an air permeable, liquid-impermeable membrane positioned between the at least one anode-cathode assembly and the external cathode terminal (825); an air impermeable removable cover over the external cathode terminal; and retaining ring for holding the at least one reservoir, at least one anode-cathode assembly, external cathode terminal, and an external anode terminal in assembly. The reservoir body is in pressure engagement with the sealing member. The reservoir body is threaded into the reservoir cap. The reservoir body comprises many reservoirs containing a fuel fluid, where the coin cell device comprises many anode-cathode assemblies, one for each reservoir. The anode-cathode assemblies: are electrically connected in series; are arranged in a generally planar array; and mechanically integrated to form one structural unit. The anode-cathode assembly for each reservoir comprises a cathode current collector associated with the biocathode and an anode current collector associated with the anode, where the anode current collector of at least one of the anode-cathode assemblies being electrically connected to the cathode current collectors of at least another one of the anode-cathode assemblies for electrically connecting the anode-cathode assemblies in series. The reservoir body is generally cylindrical, where the reservoir cavities and anode-cathode assemblies are generally sector-shaped. The external cathode terminal is air permeable. In biofuel coin cell device, each of the cathode and anode terminals comprises an end wall and a circumferential side wall extending from the end wall, and the retaining ring extends around and bridges the side walls of the terminals. The anode is a zinc or lithium-based anode. The biocathode comprises air-breathing half-cell comprising the biocathode would generate a current density of at least 16, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or more mA/cm2 when operating at room temperature, an electrode potential of 0.4 V, and a catalyst loading of 10 mg/cm2.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The combination of metal complexes comprises two or more of copper phthalocyanine, iron phthalocyanine, nickel phthalocyanine, cobalt pthalocyanine, platinum, platinum alloy, platinum black, platinum/ruthenium, copper porphyrin, iron porphyrin, nickel porphyrin, cobalt porphyrin, copper tetraazaporphyrin, iron tetraazaporphyrin, nickel tetraazaporphyrin, cobalt tetraazaporphyrin, copper tetrabenzoporphyrin, iron tetrabenzoporphyrin, nickel tetrabenzoporphyrin and/or cobalt tetrabenzoporphyrin. The hydrophobic cation comprises an ammonium-based cation, quaternary ammonium cation, alkyltrimethylammonium cation, phosphonium cation, triphenylphosphonium, pyridinium cation, imidazolium cation, hexadecylpyridinium, ethidium, viologen, methyl viologen and benzyl viologen, bis(triphenylphosphine)iminium, metal complex, bipyridyl metal complex, phenanthroline-based metal complex, (ruthenium(bipyridine)3)2+ or (iron(phenanthroline)3)3+, preferably tetraethylammonium, tetrapropylammonium, tetrapentylammonium, tetrahexylammonium, tetraheptylammonium, trimethylicosylammonium, trimethyloctyldecylammonium, trimethylhexyldecylammonium, trimethyltetradecylammonium, trimethyloctylammonium, trimethyldodecylammonium, trimethyldecylammonium, trimethylhexylammonium, tetrabutylammonium and/or triethylhexylammonium. The tetraalkyl-ammonium ion comprises an alkyltrimethyl ammonium cation or alkyltriethylammonium cation. The acid group comprises a carboxylic, a phosphonic, a phosphoric, a sulfonic, a sulfuric and/or a sulfamate or its salt. The base comprises a tertiary amine, a quaternary amine and/or a nitrogen heterocycle or its salt.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The anion exchange membrane comprising substituted benzyl-phenoxy-benzene compound of formula (V), substituted acetic acid benzyl-phenyl ester compound of formula (VI), benzene compound of formula (VII), diphenyl-sulfanyl-phenylsulfanyl-benzenethiol compound of formula (VIII), benzyl-pyridinium compound of formula (IX) or alkyl group of formula -((C-(OR34)-CH2-C-(OR35)-CH2)s)- (XI). The enzyme immobilization material is a salt-extracted tetraalkyl-ammonium modified perfluoro sulfonic acid-polytetrafluoroethylene (PTFE) copolymer having micelles of a size sufficient to constrain an enzyme in it. The micelles are substantially the same size and same shape as the enzyme. The immobilization material is a micellar hydrophobically modified polysaccharide comprising chitosan. The micellar hydrophobically modified polysaccharide has a structure of formula (II). The enzyme immobilization material is a micellar hydrophobic redox mediator modified chitosan. The immobilization material entraps the enzyme, where the immobilization material being permeable to a compound smaller than the enzyme and having the structure of formula (V), (VI), (VII), or siloxane group of formula -(O-Si-(R32)-(R33)p) (X). The immobilization material: is a micellar or inverted micellar polymer; and stabilizes the enzyme. The cathode enzyme is immobilized in an enzyme immobilization material. The immobilization material comprises: a cation modified perfluoro sulfonic acid-PTFE copolymer; and alginate, which is cation-modified alginate. The cation modified perfluoro sulfonic acid-PTFE copolymer or cation-modified alginate is modified with a hydrophobic cation larger than ammonium ion (NH4+). The hydrophobic cation comprises a quaternary ammonium cation of formula (N+-(R21)(R22)(R23)(R24)). The fuel fluid is hydrogen, ammonia, an alcohol, an allyl alcohol, an aryl alcohol, glycerol, propanediol, mannitol, glucuronate, aldehyde, a carbohydrate, glycerate, coenzyme A, acetyl co-A, malate, isocitrate, formaldehyde, acetaldehyde, acetate, citrate, L-gluconate, beta-hydroxysteroid, alpha-hydroxysteroid, lactaldehyde, testosterone, gluconate, a fatty acid, a lipid, phosphoglycerate, retinal, estradiol, cyclopentanol, hexadecanol, a long-chain alcohol, coniferyl-alcohol, cinnamylalcohol, formate (preferred), a long-chain aldehyde, pyruvate, butanal, acyl-coA, a steroid, an amino acid, flavin, NADH, flavin adenine dinucleotide, NADPH, a hydrocarbon and/or an amine. The oxidant is oxygen and/or peroxide.either R21-R25, R32-R35 = H, alkyl or hydrocarbyl (all optionally substituted) or heterocyclo, preferably hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl, more preferably ethyl, (where at least one of R21-R24 is other than H); andR21, R22, R25 = H or -(CH2)uN+R26R27R28; andR21, R22, R23, R24 = -((CH2)u)polyethyleneoxide; andR32-R33 = H, alkyl, aryl, -(substituted alkylene)-acid or its salt, -(substituted alkylene)-base or its salt, -((CH2)u)O-(CH2-CH2-O)z-Rt or -(CH2)u-O-(CH2(CH3)-CH2-O)z-Rt; orR32, R33 = H, alkyl, aryl, -(CH2)3-O-((CH2)2-O)z-CH3, -(CH2)2-C(O)-O-(CH2)2-imidazolium or -(CH2)3-O-CH2-CH(OH)-N(CH3)-(CH2)2-SO3Na;z = 3-180;Rt = alkyl, aryl (both optionally substituted) or H; eitherR26-R28 = alkyl, preferably methyl, ethyl, propyl, butyl, pentyl or hexyl; orR28 = alkylamino, -CH2N+R29R30R31, -CH2CH2N+R29R30R31 or -CH2CH2CH2N+R29R30R31, where the alkylamino group crosslinks to another repeat unit of formula (VII);u = 1-4;R29-R31 = H or alkyl;m, n, o, q, r, s = at least 10;R10 = H, alkyl, octyl, butyl, hydrocarbyl, substituted hydrocarbyl or hydrophobic redox mediator; andR11 = H, hexyl, octyl, butyl, hydrocarbyl, substituted hydrocarbyl or hydrophobic redox mediator.Provided that the average number of alkyl or substituted alkyl groups or H atoms per repeat unit is at least 0.2 or 0.1.