Patent ID: 6099984
Filing Date: 2000-08-08
Classification: H01M,Y02E

Abstract:
In 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 cathode current collector engaging said cathode face, (3) a gas permeable electrically conductive anode current collector engaging said anode face, and (4) a current-collecting plate engaging at least one of said gas permeable cathode and anode current collectors and defining a gas flow field confronting said one gas permeable current collector, said flow field comprising a plurality of lands engaging said one current collector and defining a plurality of serpentine gas flow channels, each of said channels having (a) an inlet leg for receiving gas from a supply manifold common to all said flow channels, (b) an exit leg for discharging said gas into an exhaust manifold common to all said flow channels, and (c) at least one medial leg intermediate said inlet and exit legs, said inlet, exit and medial legs for each channel bordering at least one other leg of the same channel, the improvement wherein the inlet leg of one flow channel borders the inlet leg of a first next adjacent flow channel in said flow field for substantially the entire length of said inlet legs, and the exit leg of said one flow channel borders the exit leg of a second next adjacent flow channel in said flow field for substantially the entire length of said exit legs whereby bordering inlet legs are at substantially the same pressure along their lengths and bordering exit legs are at substantially the same pressure along their length so as to prevent short-circuiting of gas from one of said flow channels to the next adjacent flow channel.