| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress transmission of hydrogen through a solid polymer electrolyte membrane from a fuel electrode side to an oxidant electrode side in starting or stop of a fuel cell system. <P>SOLUTION: In starting or stop of the fuel cell system, air supply to the oxidant electrode 5 is stopped, hydrogen gas is introduced into the fuel electrode 3, and at the same time, a fuel cell stack 2 is discharged in a circuit constituted with a changing over device 11 and a dummy load device 12, liquified carbon dioxide supplied from a liquified carbon dioxide tank 6 is vaporized with a vaporizer 7, and carbon dioxide gas (inert gas) having temperature below a freezing point is supplied to the oxidant electrode 5 from an oxidant electrode inlet 5a. Produced water contained in a solid polymer electrolyte membrane 4 is freezed, and transmission of hydrogen gas through the solid polymer electrolyte membrane 4 from the fuel electrode 3 to the oxidant electrode 5 can be suppressed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
