Patent ID: 11913124
Assignee: HITACHI ZOSEN CORPORATION
Field: Surface technology, coating (Chemistry)
Classification: CPC C  Y | IPC C

Claim 0:
1. A method of recovering performance of a water electrolysis system which includes a water electrolysis stack having a solid polymer membrane, a positive electrode provided on one surface of the solid polymer membrane, and a negative electrode provided on the other surface of the solid polymer membrane, the method comprising the steps of:
bringing an operating state of the water electrolysis system into a state of low-temperature operation in which a temperature of water fed to the water electrolysis stack is lower than a temperature of water fed to the water electrolysis stack during ordinary operation in which water electrolysis is carried out by the water electrolysis stack;
in the state of the low-temperature operation, passing an electric current through each of the positive electrode and the negative electrode; and
in the state of the low-temperature operation, recovering the solid polymer membrane wherein recovering the solid polymer membrane includes removing contaminant in the solid polymer membrane while maintaining the polarity of the electric current passed through the positive and negative electrodes.