A fuel cell and battery voltage controlling method in a hybrid fuel cell/battery system

A method for controlling a fuel cell system is disclosed. One embodiment of the method comprises supplying an amount of fuel and an amount of oxidant to a fuel cell stack. The amount of fuel supplied to the fuel cell stack is controlled to attain a desired voltage output, such that the desired voltage is at least partially based upon an input current and voltage for a battery in electrical communication with the fuel cell stack. A vehicle power system is also disclosed.