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A PEM fuel cell having a current collector comprising a polymer composite and a diffusion media engaging said polymer composite. The polymer composite has a hyperconductive surface layer engaging the diffusion media to reduce the contact resistance therebetween. The hyperconductive surface layer is

A PEM fuel cell having a current collector comprising a polymer composite and a diffusion media engaging said polymer composite. The polymer composite has a hyperconductive surface layer engaging the diffusion media to reduce the contact resistance therebetween. The hyperconductive surface layer is formed by depositing or smearing an electrically-conductive material on the surface of the polymer composite.

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1. In a Proton Exchange Membrane fuel cell having at least one cell comprising(a) a pair of opposite polarity electrodes each having a first face exposed to a fuel cell reactant and a second face engaging a membrane-electrolyte interjacent said electrodes,(b) a porous, electrically-conductive media

1. In a Proton Exchange Membrane fuel cell having at least one cell comprising(a) a pair of opposite polarity electrodes each having a first face exposed to a fuel cell reactant and a second face engaging a membrane-electrolyte interjacent said electrodes,(b) a porous, electrically-conductive media engaging said first face for distributing said reactant over, end conducting electrical current from, said first face, and (3) a current collector engaging said media for conducting electrical current from said media said current collector comprising a composite having a first conductivity and comprising corrosion-proof, electrically conductive filler dispersed throughout an oxidation-resistant and acid-resistant, water-insoluble polymeric matrix, the improvement comprising said current collector comprising a metal substrate supporting said composite and an oxidation-resistant and acid-resistant hyperconductive surface layer on said composite and engaging said media, said hyperconductive surface layer having a second conductivity greater than said first conductivity and serving to shunt electrical current passing through said media into said surface layer to such of said filler in said composite as resides at the interface between said surface layer and said composite, and thereby reduce the contact resistance that would otherwise exist between said composite and said media absent said surface layer. 2. A fuel cell according to claim 1 wherein said substrate comprises a first acid-soluble metal underlying a second acid-insoluble, oxidizeable metal layer engaging said composite. 3. A fuel cell according to claim 1 wherein said metal is selected from the group consisting of titanium, stainless steel, and aluminum. 4. In a Proton Exchange Membrane fuel cell having at least one cell comprising(a) a pair of opposite polarity electrodes each having a first face exposed to a fuel cell reactant and a second face engaging a membrane-electrolyte interjacent said electrodes,(b) a porous, electrically-conductive media engaging said first face for distributing said reactant over, and conducting electrical current from, said first face, and (3) a current collector engaging said media for conducting electrical current from said media, said current collector comprising a composite having a first conductivity and comprising corrosion-proof, electrically conductive filler dispersed throughout an oxidation-resistant and acid-resistant, water-insoluble polymeric matrix, the improvement comprising an oxidation-resistant and acid-resistant hyperconductive surface layer on said composite and engaging said media, said hyperconductive surface layer comprising a plurality of oxidation-resistant and acid-resistant, electrically-conductive particles adhering to a surface of said composite confronting said media and having a second conductivity greater than said first conductivity to shunt electrical current passing through said media into said surface layer to such of said filler in said composite as resides at the interface between said surface layer and said composite, and thereby reduce the contact resistance that would otherwise exist between said composite and said media absent said surface layer. 5. A fuel cell according to claim 4 wherein said filler is selected from the group consisting of gold, platinum, graphite, conductive carbon, palladium, rhodium, ruthenium, and the rare earth metals. 6. A fuel cell according to claim 4 wherein said filler comprises a plurality of particles. 7. A fuel cell according to claim 6 wherein said particles are fibrillose and oriented in the general direction that the electrical current flows through the composite. 8. A fuel cell according to claim 4 wherein said current collector is comprised entirely of said composite. 9. A fuel cell according to claim 4 wherein said filler comprises continuous fibers that extend through the thickness of said composite. 10. A fuel cell according to claim 4 wherein at least one of said current collectors is a bipolar plate confronting the anode of one said cells and the cathode of the next adjacent cell. 11. A fuel cell according to claim 4 wherein said polymer matrix is selected from the group consisting of epoxies, polyamide-imides, polyether-imides, polyphenols, fluro-elastomers, polyesters, phenoxy-phenolics, epoxide-phenolics, acrylics, and urethanes. 12. A proton exchange membrane fuel cell according to claim 4 wherein said particles comprise graphite. 13. A proton exchange membrane fuel cell according to claim 4 wherein said particles are at least partially embedded in said surface. 14. In a Proton Exchange Membrane fuel cell having at least one cell comprising(a) a pair of opposite polarity electrodes each having a first face exposed to a fuel cell reactant and a second face engaging a membrane-electrolyte interjacent said electrodes,(b) a porous, electrically-conductive media engaging said first face for distributing said reactant over, and conducting electrical current from, said first face, and (3) a current collector engaging said media for conducting electrical current from said media said current collector comprising a composite having a first conductivity and comprising corrosion-proof, electrically conductive filler dispersed throughout an oxidation-resistant and acid-resistant, water-insoluble polymeric matrix, the improvement comprising an oxidation-resistant and acid-resistant hyperconductive surface layer on said current collector and engaging said media, said hyperconductive surface layer comprising a continuous, oxidation-resistant, and acid-resistant film on the surface of said composite confronting said media and having a second conductivity greater than said first conductivity to shunt electrical current passing through said media into said surface layer to such of said filler in said composite as resides at the interface between said surface layer and said composite, and thereby reduce the contact resistance that would otherwise exist between said composite and said media absent said surface layer.