Patent ID: 8338042

Claim:
A fuel cell system comprising: a fuel cell that includes a fuel electrode and an oxidizer electrode, and an electrolyte disposed between the fuel electrode and the oxidizer electrode, the fuel cell generating electric power when fuel gas and oxidizing gas are supplied to the fuel electrode and the oxidizer electrode, respectively; a fuel-gas circulation path connecting an inlet of the fuel electrode to an outlet of the fuel electrode, the fuel gas supplied through the inlet and discharged from the outlet; a fuel-gas circulation pump on the fuel-gas circulation path; air replacement state recognizing means for determining a gas distribution state of the fuel electrode, wherein the gas distribution state includes a state in which hydrogen and air are unevenly distributed in at least the fuel electrode, a state in which air has displaced hydrogen in the fuel electrode, and a state in which hydrogen has not been displaced in the fuel electrode; and a start control device configured to select a fuel cell restart operation based on the gas distribution state determined by the air replacement state recognizing means and to operate the fuel-gas circulation pump and a supply of the fuel gas based on the fuel cell restart operation selected.