FUEL CELL SYSTEM AND METHOD FOR CONTROLLING THE SAME

A fuel cell system includes a fuel cell stack that produces electric power and water through an electro-chemical reaction of hydrogen and air. A controller of the fuel cell system calculates an amount of water in the fuel cell stack based on output power of the fuel cell stack and a maximum amount of residual water to which the amount of water in the fuel cell stack converges over time. The fuel cell system may detect the amount of water in the fuel cell stack in real time.