Patent ID: 7344790

Claim:
A fuel cell system comprising: an anode side humidifier for humidifying a fuel gas and a cathode side humidifier for humidifying a reactant gas, wherein each humidifier includes plurality of hollow fiber membrane modules for migrating moisture between a supply gas, which is supplied to a fuel cell, and an exhaust gas, which is exhausted from the fuel cell to thereby humidify the supply gas: a pair of heads which hold both ends of said hollow fiber membrane modules, a connecting member which connects each of the heads, and a device for warming the supply gas composed of conduits through which a cooling medium exhausted from the fuel cell is passed, said device including a first conduit disposed along said connecting member, a second conduit disposed around an outer circumference of one of said pair of heads, and a third conduit disposed around an outer circumference of the other of said pair of heads; wherein said device for warming the supply gas is configured to first warm a humidifier at an outlet side of the supply gas, and subsequently warm a humidifier at an inlet side of the supply gas.