Abstract: A self-humidifying polymer electrolyte membrane (PEM) fuel cell assembly has an ion-exchange membrane interposed between hydrogen and oxygen diffusion layers to form a membrane electrode assembly (MEA). The MEA is in turn interposed between a pair of current collector plates having flow field channels for flowing the reactants adjacent the respective diffusion layers to produce corresponding anodic and cathodic electrochemical reactions. Various embodiments of the assembly incorporate one or more of the following features: interdigitated flow field channels, countercurrent reactant flows, opposing channel alignment, and uncatalyzed membrane hydration enhancement zones.

Abstract: An improved molding composition is provided for compression molding or injection molding a current collector plate for a polymer electrolyte membrane fuel cell. The molding composition is comprised of a polymer resin combined with a low surface area, highly-conductive carbon and/or graphite powder filler. The low viscosity of the thermoplastic resin combined with the reduced filler particle surface area provide a moldable composition which can be fabricated into a current collector plate having improved current collecting capacity vis-a-vis comparable fluoropolymer molding compositions.