CONTROL METHOD FOR FUEL CELL SYSTEM

A control method for a fuel cell system includes: acquiring a poisoning rate of an electrode catalyst of a fuel cell; performing a potential maintaining operation of maintaining a potential of the fuel cell in a first potential range when the poisoning rate of the electrode catalyst is greater than a prescribed value α; and performing a potential changing operation of repeating a cycle in which the potential of the fuel cell is changed between an upper-limit potential and a lower-limit potential of a second potential range which is higher than the first potential range after the potential maintaining operation has been performed.