Patent ID: 8101309
Filing Date: 2012-01-24
Classification: H01M,Y02E

Abstract:
1. A fuel cell system comprising: a fuel cell for performing power generation by electrochemical reactions of an oxygen-containing gas and a fuel gas supplied to the fuel cell, the fuel cell including a solid polymer electrolyte membrane comprising hydrocarbon material, a cathode, and an anode, an oxygen-containing gas flow field being formed in the fuel cell for supplying the oxygen-containing gas to the cathode, a fuel gas flow field being formed in the fuel cell for supplying the fuel gas to the anode, an oxygen-containing gas supply apparatus for supplying the oxygen-containing gas to the oxygen-containing gas flow field; a fuel gas supply apparatus for supplying the fuel gas to the fuel gas flow field; a scavenging gas supply apparatus for supplying the air as a scavenging gas to the fuel gas flow field; and a control device, wherein the control device includes: a voltage detection unit for detecting a voltage of the fuel cell after operation of the fuel cell is stopped; and a scavenging control unit for directing the scavenging gas supply apparatus to start a scavenging procedure in the fuel gas flow field, wherein the scavenging control unit only directs the scavenging gas supply apparatus to start the scavenging procedure after the detected voltage initially decreases, increases subsequent to the initial decrease with time substaintially only by leakage of the oxygen containing gas toward the anode and leakage of the fuel gas toward the cathode through the electrolyte membrane, and decreases subsequent to the increase until the detected voltage reaches a preset voltage or less.