Patent ID: 8367270

Claim:
A pair of fluid flow plates for use with a generally planar polymer membrane electrolyte of a proton exchange membrane fuel cell stack, said plates comprising: a first fluid flow plate comprising a plurality of oxidant channels separated by first lands, and a second fluid flow plate comprising a plurality of fuel channels separated by second lands, wherein at least one of said second lands has a cross sectional width wider than a cross sectional width of at least one of said first lands, each of said oxidant channels and each of said fuel channels are formed with a multiple of alternating angles and wherein the multiple of alternating angles is different for said oxidant channels and said fuel channels, and are configured such that a respective oxidant or fuel flowpath formed by corresponding said channels and lands defines a pattern of overlapping, aligned crests between the first lands and the second lands, where said corresponding lands are arranged such that when said second fluid flow plate is placed in cooperation with said first fluid flow plate with a membrane electrode assembly that includes said generally planar polymer membrane electrolyte situated therebetween, said oxidant and fuel lands that are adjacent said membrane electrode assembly are arranged relative to one another to increase overlapping of their respective oxidant and fuel lands and wherein the crest alignment between the first lands and the second lands is achieved using at least one equation selected from the group consisting of (Ac+Af)=N*p+/−Wc or(Ac−Af)=+/−N*p+/−Wc, wherein Ac is the amplitude of said second lands, Af is the amplitude of said first lands, N is an integer, p is a pitch, and Wc is the land width of the second lands.