SOLID POLYMER FUEL CELL STACK AND METHOD FOR OPERATING THE SAME, AND AIR VENT VALVE

摘要

A fuel cell stack comprises membrane electrode complexes (3) in which gas diffusion electrodes (2a, 2b) are arranged on both sides of a solid polymer membrane (1) and a reactant gas supply separators (5) interposed between the membrane electrode complexes (3). The reactant gas supply separators (5) each have a first surface having a fuel gas supply groove (9a) for supplying a fuel gas, a second surface having an oxidizer gas supply groove (9b) for supplying an oxidizer gas, and a water supplying means for supplying water to the fuel gas supply groove (9a). The water supply means has a water supply groove (15) for introducing water from a water supply manifold (14) disposed on the second surface, communication holes (16) for communication of the second surface with the first surface, and a buffer section (17) having a porous body (20) for uniformly distributing water from the water supply groove (15) to the communication holes (16). The porous body (20) extends over the second surface. The water flows in the porous body (20) along the second surface. Therefore water can be supplied uniformly to the fuel gas supply grooves (9a) of the reactant gas supply separator (5).