摘要 |
There is provided an air-breathing fuel cell stack in which a sufficient amount of oxygen is supplied to an oxygen flow field plate so as to enhance an electric power-generating ability, and besides material costs can be reduced. An air-breathing fuel cell stack includes a pair of end plates, a plurality of unit cells, which are provided between the two end plates, a fuel distribution manifold provided in central portions of the unit cells so as to supply fuel thereto, a single tie bolt passing through a central portion of the fuel distribution manifold and the central portions of the unit cells so as to clamp the fuel cell components together into a unitary construction, and a pair of fixing bolts threaded respectively on both end portions of the tie bolt through O-rings, washers or the like to clamp the plurality of unit cells between the two end plates. The unit cell includes a polymer electrolyte membrane, an oxygen electrode and a fuel electrode disposed respectively on both sides of the polymer electrolyte membrane in opposed relation to each other, a flow field plate disposed adjacent to the oxygen electrode, and a pair of current collector plates contacting outer sides of the flow passage and fuel electrode, respectively. The end plate, the end gasket and the current collector plate have a communication passage which is open outwardly, and communicates with the oxygen flow field plate of the cell portion. |