Patent ID: 8415062

Claim:
A fuel cell system comprising: a fuel cell including a solid polymer electrolyte membrane, and a cathode passage and an anode passage, with the solid polymer electrolyte membrane being interposed between the cathode passage and the anode passage, the fuel cell supplying cathode gas to the cathode passage and supplying anode gas to the anode passage to generate electric power; a cathode supply passage through which the cathode gas is supplied to the cathode passage; a cathode discharging passage through which cathode discharged gas is discharged from the cathode passage; an anode supply passage through which the anode gas is supplied to the anode passage; an anode discharging passage through which anode discharged gas is discharged from the anode passage; a pair of cathode shutoff units each installed in the cathode supply passage and the cathode discharging passage; an anode shutoff unit installed in the anode supply passage; an anode discharging unit installed in the anode discharging passage; a discharged gas processing unit installed in a downstream side of both the cathode shutoff unit of the cathode discharging passage and the anode discharging unit of the anode discharging passage, the discharged gas processing unit configured to process the anode gas and the cathode gas and discharge the processed anode gas and the processed cathode gas outside of the fuel system; and a control unit configured to seal the cathode passage by the pair of cathode shutoff units and simultaneously seal the anode passage by the anode shutoff unit and the anode discharging unit, at the time of stoppage of electric power generation of the fuel cell, wherein the control unit releases the sealing of the cathode passage by the pair of cathode shutoff units, at the time of start-up of the fuel cell system, and then releases the sealing of the anode passage by the anode discharging unit, thereby performing a purge process to allow discharge of the anode gas.