| 摘要 |
PROBLEM TO BE SOLVED: To decrease amount of unreacted hydrogen exhausted from a fuel cell. SOLUTION: An exhaust gas pass valve 505 equipped in hydrogen exhaust gas pass 415c of a fuel cell (FC stack) 200, opening and closing the hydrogen exhaust gas pass 415c, and a hydrogen sensor (remaining hydrogen concentration detection means) 601 detecting hydrogen concentration in the FC stack 200, are equipped. When the hydrogen concentration detected by the hydrogen sensor 601 is a 1st predetermined hydrogen concentration d1 or less, the exhaust gas pass valve 505 is opened. When it is a 2nd predetermined hydrogen concentration d2 or more which is higher than the 1st predetermined hydrogen concentration d1 the exhaust gas pass valve 505 is closed. Thus, by intermittently supplying hydrogen to the FC stack 200 from a hydrogen supply means 100, when hydrogen concentration is high, hydrogen can be made to fully react by keeping hydrogen rich gas in the FC stack 200, and a remaining gas can be exhausted after hydrogen concentration becomes low. |
