TEMPERATURE CONTROL DEVICE FOR FUEL CELL

PURPOSE:To control the supply amount of a thermo-medium from a heating tank in a wide range by divergence control using a three-way valve, by furnishing a bypass through which the thermo-medium flows divergently through the three-way valve in a position nearer the heating tank on a main circulation line, and thereby allowing the heating tank to function as a buffer tank. CONSTITUTION:A heating tank 11 having an upper space functions as a buffer tank and the ratio of the rate of thermo-medium flow heated to 170 deg.C from the heating tank 11, which converges with the suction side of a circulation pump 13, to the rate of thermo-medium flow from a bypass 27 becomes controllable as desired by the use of a three-way selector valve. When this fuel cell concerned 1 is to be held at a standby temp. around 130 deg.C, therefore, it is practicable to sink the temp. of thermo-medium flowing through the circulation line down to around 130 deg.C while the temp. of the thermo-medium 12 stored in the heating tank 11 is kept at 170 deg.C through utilization of the heat radiated from the circulation system leading via the bypass 27, and the fuel cell temp. can be maintained stably and accurately at the standby temp. by compensating the downward overshooting temp. of the thermo-medium with a high temp. thermo-medium fed from the heating tank 11.