Patent ID: 9431669
Filing Date: 2016-08-30
CPC Classification: H01M,Y02E

Claim Text:
1. A method for stopping a fuel cell system that includes: a fuel cell that generates electric power by supplying fuel gas to an anode and supplying oxidizing gas to a cathode; a fuel gas supply channel in which fuel gas supplied to the anode flows; a fuel gas discharge channel in which anode discharge gas from the anode flows; an oxidizing gas discharge channel in which cathode discharge gas from the cathode flows; an inert gas storage portion that connects the oxidizing gas discharge channel and the fuel gas supply channel; a supply shutoff valve that is provided to the fuel gas supply channel and cuts off new supply of fuel gas to the anode; a discharge shutoff valve that is provided to the fuel gas discharge channel and cuts off discharge of anode discharge gas from the anode to outside of the system; and an influx shutoff valve that cuts off influx of cathode discharge gas from the inert gas storage portion to the fuel gas supply channel, the method comprising the steps of: cutting off new supply of fuel gas to the anode and discharge of anode discharge gas from the anode to outside of the system by closing the supply shutoff valve and the discharge shutoff valve, after a stop command for the fuel cell system; continuing electric power generation by using the fuel gas remaining in the fuel gas discharge channel, the fuel gas discharge channel and the anode, and reducing a pressure inside the anode by way of the fuel cell in a state in which the supply of fuel gas to the anode and the discharge of anode discharge gas from the anode are cut off by closing the supply shutoff valve and the discharge shutoff valve according to the step of cutting off; closing the influx shutoff valve, and storing, in the inert gas storage portion, inert gas discharged from the cathode to the oxidizing gas discharge channel in the step of continuing electric power generation; and opening the influx shutoff valve while closing the supply shutoff valve and the discharge shutoff valve, thereby introducing inert gas stored inside of the inert gas storage portion to inside of the fuel gas supply channel, after the step of continuing electric power generation.