Patent ID: 6905793

Claim:
In a fuel cell stack comprising a plurality of substantially planar fuel cell units, each said fuel cell unit comprising an anode layer, a cathode layer and an electrolyte layer disposed there between, and a separator plate having an anode facing surface and a cathode facing surface, said separator plate disposed between said anode layer of one of said fuel cell units and a cathode layer of an adjacent said fuel cell unit, the improvement comprising: said separator plate comprising two joined together coextensive separator plate elements having perpendicularly disposed corrugated regions and forming a coolant chamber there between, each said separator plate element having an electrode facing face and a coolant facing face and having two flattened peripheral seal regions extending along opposed edges of said separator plate elements, said opposed edges extending perpendicular to a direction of corrugation of said corrugated region; a first gasket material disposed in said flattened peripheral seal regions on said coolant facing face of one of said separator plate elements and said flattened peripheral seal regions on said electrode facing face of said other said separator plate element; a second gasket material disposed in said flattened peripheral seal regions on opposite faces of said separator plate elements on which said first gasket material is disposed; a filler material disposed within said corrugations on said coolant facing faces along non-flattened edges of said separator plate elements, whereby a peripheral seal is effected between said separator plate elements; and coolant means for introducing a coolant into said coolant chamber.