Abstract: A method for repairing a fuel cell stack having a plurality of individual cells involves the steps of: a) identifying at least one degraded individual cell in the fuel cell stack; and b) deactivating the at least one degraded individual cell.

Abstract: A method for repairing a fuel cell stack having a plurality of individual cells involves the steps of: a) identifying at least one degraded individual cell in the fuel cell stack; and b) deactivating the at least one degraded individual cell.

Abstract: A fuel cell system is provided having a plurality of fuel cells combined to form a fuel cell stack. The fuel cell system is characterized in that at least one fuel cell is a redox flow fuel cell having an electrode assembly, which electrode assembly has a proton-permeable separator, which separator is arranged between an anode region and a cathode region. The redox flow fuel cell has a regenerator spatially separated from the electrode assembly, and a water-forming reaction of the redox flow fuel cell occurs in the regenerator. The redox flow fuel cell also has at least one oxidation-fluid delivery unit for feeding oxidation fluid into the regenerator in order to perform the water-forming reaction in the regenerator of the redox flow fuel cell. The redox flow fuel cell also has a pumping circuit, comprising a pumping device and a pumping line, for transporting an electrochemical storage system through the cathode region or the anode region of the redox flow fuel cell and through the regenerator.