Abstract: A reactant flow system for a proton exchange membrane (PEM) fuel cell stack using a water-soluble fuel is described. The flow system includes the use of single-pass or multi-pass, flow channels. A flow channel section having at least one adjacent channel section whose reactant flows in an opposite direction thereto. The system has respective reactant inlets that are effectively adjacent to reactant outlets of the adjacent channel section. Restrictions are used at the reactant inlets to assure substantially uniform reactant flow among all of the flow channels.

Abstract: A reactant flow system for a proton exchange membrane (PEM), hydrogen-air, fuel cell stack, is described. The flow system includes the use of single-pass or multi-pass, flow channels. A flow channel section having at least one adjacent channel section whose reactant flows in an opposite direction thereto. The system has respective reactant inlets that are effectively adjacent to reactant outlets of the adjacent channel section. Restrictions are used at the reactant inlets to assure substantially uniform reactant flow among all of the flow channels. The PEM fuel cell stack has a mechanism for removing heat therefrom in order to prevent drying out of the electrolyte membrane.

Abstract: An improved interface configuration for use between adjacent elements of a fuel cell stack. The interface is impervious to gas and liquid and provides resistance to corrosion by the electrolyte of the fuel cell. A multi-layer arrangement for the interface provides bridging electrical contact with a hot-pressed resin filling the void space.

Abstract: The present invention relates to improved elements for use in fuel cell stacks, and more particularly, to a stack having a corrosion-resistant, electrally conductive, fluid-impervious interface member therein.

Abstract: A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.

Abstract: An improved interface configuration for use between adjacent elements of a fuel cell stack. The interface is impervious to gas and liquid and provides resistance to corrosion by the electrolyte of the fuel cell. A multi-layer arrangement for the interface provides bridging electrical contact with a hot-pressed resin filling the void space.

Abstract: A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.