Patent ID: 8735011

Claim:
A fuel cell system comprising: a fuel cell that obtains electric power through electrochemical reaction; a temperature detecting device that detects a temperature of the fuel cell; a heat medium circulating path in which heat medium for exchanging heat with the fuel cell is circulated; a heat medium pump for circulating the heat medium in the heat medium circulating path; a heat exchanging device that cools down the heat medium, the heat exchanging device being disposed on the heat medium circulating path; a heat exchanging device bypass in which the heat medium is circulated to bypass the heat exchanging device on the heat medium circulating path, wherein the heat exchanging device bypass is separate from, but in fluid communication with, the heat medium circulating path, the heat exchanging device bypass creating a flow path for the heat medium that does not include the heat exchanging device; a heat medium flow rate controlling device, which is programmed to control a flow rate of at least one of the heat medium flowing through the heat exchanging device bypass and the heat medium flowing through the heat medium circulating path, based on the temperature of the fuel cell detected by the temperature detecting device; a heating device that heats the heat medium, the heating device being disposed on the heat exchanging device bypass; a flow rate detecting device that detects a flow rate of the heat medium flowing through the heat exchanging device bypass, the flow rate detecting device being disposed on the heat exchanging device bypass; and a heat controlling device, which is programmed to control the heating device based on the flow rate of the heat medium detected by the flow rate detecting device.