Patent ID: 8227134

Claim:
A self-hydrating membrane electrode assembly (MEA) for fuel cells, wherein said MEA comprises: (i) a cathode comprising an electrically conducting material having a cathode catalytic material on a portion of a first surface thereof, said cathode catalytic material comprising a catalytically effective amount of a mixture of at least one catalyst component and at least one ion conducting material to produce cations from a hydrogen-containing fuel supply; (ii) an anode comprising an electrically conducting material having an anode catalytic material on a portion of a first surface thereof, said anode catalytic material comprising a catalytically effective amount of a mixture of at least one catalyst component and at least one ion conducting material to produce anions from an oxygen-containing fuel supply; and (iii) a separator adjacent to and interposed between said cathode and said anode, said separator comprising an ion conducting material having a first surface and a second surface opposite said first surface, a portion of said first surface is adjacent to and in contact with said first surface of said cathode, and a portion of said second surface is adjacent to and in contact with said first surface of said anode; wherein a portion of said first surface of said separator contacting said cathode directly contacts the first surface of the cathode without contacting said cathode catalytic material, a portion of said second surface of said separator contacting said anode directly contacts the first surface of the anode without contacting said anode catalytic material, and said portions directly contacting said anode and said cathode without contacting said catalytic materials are opposite each other, thereby providing a portion of said separator that permits water to pass from the cathode side of said separator to the anode side of said separator, and further wherein said cathode produces water in an amount effective to sustain hydration of said anode, wherein said separator comprises a polymer electrolyte membrane, wherein the thickness of said polymer electrolyte membrane is between 1 mil and 7 mils.