Patent ID: 7112385
Filing Date: 2006-09-26
Classification: H01M,Y02E

Abstract:
1. A PEM fuel cell comprising (1) a proton exchange membrane having opposing cathode and anode faces on opposite sides of said membrane, (2) a gas-permeable electrically-conductive current collector engaging at least one of said faces, and (3) a current-collecting plate engaging said gas-permeable current collector, said current collecting plate having a gas flow-field confronting said gas-permeable current collector, said gas flow-field comprising a plurality of lands engaging said gas-permeable current collector and separating a plurality of gas flow-channels one from the next, said gas flow-channels each having (a) an inlet end communicating with a supply manifold that supplies a reactant gas at a first pressure to all of said gas flow-channels, and (b) an exit end communicating with an exhaust manifold that receives said gas from said gas flow-channels, a first flow-restrictor in a first gas flow-channel to reduce said first pressure to a second pressure in said first gas flow-channel downstream of said first flow-restrictor that is less than said first pressure, and a second flow-restrictor in a second flow-channel next adjacent said first flow-channel for maintaining a third pressure in said second gas flow-channel upstream of said second flow-restrictor that is greater than said second pressure and sufficient to drive said gas from said second gas flow-channels into said first flow-channel through such of said gas-permeable current collector as engages the land separating said first gas flow-channel from said second gas flow-channel.