Patent ID: 7754391

Claim:
A stack of fuel cells being a fuel gas non-circulating-type where a supply of a fuel gas is not recirculated, said stack of fuel cells comprising: a cell stack body that includes multiple unit cells laid one upon another and has a fuel gas flow path formed therein to make a flow of the fuel gas; multiple connection mechanisms that are provided with the cell stack body and function to connect the fuel gas flow path formed in the cell stack body with either outside of the cell stack body or a fuel gas supply source and disconnect the fuel gas flow path in the cell stack body from both the outside of the cell stack body and the fuel gas supply source; and a connection mechanism control module that, in a normal operating condition, sets at least one connection mechanism among the multiple connection mechanisms in a disconnected state from both the outside of the cell stack body and the fuel gas supply source, while setting residual connection mechanisms in a connecting state with the fuel gas supply source, when impurities accumulate, said connection mechanism control module changing over the at least one connection mechanism, which is set in the disconnected state from both the outside of the cell stack body and the fuel gas supply source, to connect the fuel gas flow path to the outside of the cell stack body, wherein the connection mechanism control module sequentially selects different connection mechanisms as the at least one connection mechanism, which is set in the disconnected state from both the outside of the cell stack body and the fuel gas supply source, to be successively connected with the outside of the cell stack body, and each fuel cell is driven with the supply of the fuel gas kept inside in the normal operating condition.