GAS FEEDING/DISCHARGING DEVICE FOR FUEL CELL

PROBLEM TO BE SOLVED: To smoothly guide the fuel gas and air to electrodes without developing excessive differential pressure by providing small-diameter valves in parallel with a case-fuel electrode equalizing valve and a case-air electrode equalizing valve respectively. SOLUTION: A case-fuel electrode equalizing small valve 4 smaller in diameter than a case-fuel electrode equalizing valve 3 is provided on a small-diameter piping 4P bypassing the case-fuel electrode equalizing valve 3 in this gas feeding/ discharging device for a fuel cell. A case-air fuel equalizing small valve 11 smaller in diameter than a case-air electrode equalizing valve 10 is provided on a small-diameter pipe 11P bypassing the case-air electrode equalizing valve 10. Four valves 3, 4, 10, 11 are opened, the differential pressure is suppressed by the low fluid resistance of the case-fuel electrode equalizing valve 3 and the case-air electrode equalizing valve 10, and the nitrogen pressure is boosted on a fuel electrode, an air electrode, and the case. The equalizing valves 3, 10 are closed and the equalizing small valves 4, 11 are opened, and the differential pressure is suppressed to suppress the nitrogen flow. Nitrogen can be switched to reaction gas without generating an excessive differential pressure.