Patent ID: 8293427

Claim:
A separator unit for separating adjacent stacked fuel cells in a fuel cell stack, the separator unit comprising: a flat gas barrier sheet member; a collector in the form of a flat sheet with a plurality of openings for gas passage therethrough, the collector having a first flat surface for contact with an electrode of one of the adjacent stacked fuel cells to collect power from the electrode; and a plurality of metal linear ribs arranged spaced and in parallel across a second flat surface of the collector, opposite the one flat surface, the metal linear ribs being bonded to the second flat surface of the collector and being in contact with a flat surface of the gas barrier sheet member to form a plurality of gas flow channels in a spacing between the gas barrier sheet member and the collector, with the gas flow channels separated by the metal linear ribs; and wherein the openings in the collector each have a rhombus shape with a major diagonal dimension LW and a minor diagonal dimension SW, wherein each metal linear rib has a thickness H equal to the spacing between the gas barrier sheet member and the collector and wherein a relationship between LW, SW and H is: H<SW<LW.