Fuel cell system

A fuel cell system comprising:

• a fuel cell body having an anode electrode supplied with fuel gas containing hydrogen and a cathode electrode supplied with oxidizer gas;
• catalyst degradation-suppressing means for interrupting a supply of oxidizer gas to the cathode electrode after disconnecting an external load from the fuel cell body and allow a load current, generated by the fuel cell body, to be extracted by an internal load while supplying the fuel gas to the anode electrode;
• hydrogen supply stop means for interrupting a supply of fuel gas to the anode electrode except for residual hydrogen being supplied thereto during a period in which the load current is extracted by the internal load;
• and
• load current control means for controlling a target load current such that after the supply of fuel gas to the anode electrode is stopped, a pressure inside the anode electrode is maintained at a target pressure.

A method of operating a fuel cell system, comprising:

• providing a fuel cell body having an anode electrode supplied with fuel gas containing hydrogen and a cathode electrode supplied with oxidizer gas;
• providing an internal load;
• interrupting a supply of oxidizer gas to the cathode electrode after disconnecting an external load from the fuel cell body;
• connecting the internal load to the fuel cell body to allow a load current to be extracted from the fuel cell body while supplying the fuel gas to the anode electrode;
• interrupting a supply of the fuel gas to the anode electrode except for residual hydrogen being supplied thereto during a period in which the load current is extracted by the internal load;
• and
• controlling a target load current such that after the supply of fuel gas to the anode electrode is interrupted, a pressure inside the anode electrode is maintained at a target pressure.