Patent ID: 6593022
Filing Date: 2003-07-15
Classification: H01M,Y02E

Abstract:
A proton exchange membrane fuel cell stack comprising a membrane electrode assembly layer having a first surface and a second surface wherein a fuel gas flow field comprising at least one fuel gas flowpath is adjacent the first surface and an oxidant gas flow field comprising at least one oxidant gas flowpath is adjacent the second surface, the flowpaths having parallel transversely spaced and longitudinally extending flow channels interconnected in the vicinity of the ends of the flow channels to form the flowpaths, the improvement comprising:said membrane electrode assembly layer being provided, on both the first and second surfaces, with an array of spaced flow channel couplings, each coupling interconnecting at least two adjacent flow channels on the same surface of the assembly to form flowpaths for each of a fuel gas and an oxidant gas on respective surfaces of the assembly, wherein the couplings for the oxidant gas flow channels are transversely offset from the couplings for the fuel gas flow channels and wherein the membrane electrode assembly layer is undulate.