Method and regulation apparatus for operating a fuel cell or a fuel cell stack

A method of operating a fuel cell or a fuel cell stack wherein the fuel cell or fuel cell stack can output an electrical maximum power dependent on the operating temperature for a given fuel gas flow, and which exhibits aging in dependence on the operating duration which brings about an increase of the electrical internal resistance with progressive operating duration, wherein in the method a starting value (T0) of the operating temperature is predefined which is smaller than the maximum specified operating temperature (Tmax) for the fuel cell or the fuel cell stack and the fuel cell or the fuel cell stack is regulated such that the decrease of the electrical power output as a consequence of aging is partly or completely compensated in that the operating temperature (T) of the fuel cell or of the fuel cell stack is increased with progressive aging;

• wherein the decrease of the output electrical power as a consequence of aging is compensated, in that the fuel gas flow (Pgas) is increased with progressive aging;
• and with a starting value (Pgas0) being predefined for the fuel gas flow which starting value is smaller than the maximum specified fuel gas flow (Pmax) for the fuel cell or the fuel cell stack.