Patent ID: 9660278
Date: 2017-05-23
CPC Classifications: H01M,Y02E

Claim:
1. A fuel cell system comprising: a fuel cell stack including a cathode side and an anode side; an injector for injecting hydrogen gas into the anode side of the fuel cell stack; a water separation device receiving an anode exhaust gas from the anode side of the fuel cell stack, said water separation device including a water holding reservoir and a bleed/drain valve; and a controller programmed to control the injector and the bleed/drain valve, said controller opening the bleed/drain valve in the water separation device and determining when the bleed/drain valve transitions from draining water to bleeding anode exhaust gas, wherein the controller uses the bleeding of the anode exhaust gas through the bleed/drain valve and the determination of when the bleed/drain valve transitions from draining water to bleeding anode exhaust gas in a nitrogen accumulation model such that the model determination of the amount of nitrogen in the anode side of the stack has increased accuracy, wherein the controller compares the flow rate through the water separation device and the flow rate through the injector to determine when the bleed/drain valve transitions from draining water to bleeding the anode exhaust gas.