Patent ID: 9178224
Filing Date: 2015-11-03
Classification: H01M,Y02E

Abstract:
1. A fuel cell stack of at least two fuel cells, each fuel cell comprising a unitized electrode assembly (UEA) comprising a thrifted electrolyte membrane disposed between a pair of electrodes forming a membrane electrode assembly (MEA), the MEA being framed on a sub-gasket such than an overlap exists between an outer perimeter of the MEA and an inner perimeter of the sub-gasket defining an overlap area, the framed MEA being disposed between a pair of gas diffusion media (DM), a pair of stamped flow-field plates, one on each side of a UEA such that flow-field plates of adjacent fuel cells align to form a bipolar plate comprising an active region, a seal region, and an overlap region, said overlap region disposed between an outer perimeter of the active region and an inner perimeter of the seal region and substantially corresponding in area to the overlap area, wherein the active region comprises a configuration of channel and land features and the overlap region comprises a modified configuration of channel and land features, “modified” being with respect to the configuration of channel and land features in the active region, which permit a level of mechanical pressure sufficient to seal the overlap region and to substantially prevent coolant and reactant bypass without impeding coolant and reactant flow in the active area.