For an air-cooled self-humidifying PEMFC, anode purge can blow out the accumulated liquid water from fuel cell, but the water management ability islimited. So the water management of fuel cell is achieved by adjusting the air flow of the cathode. Therefore, water management andthermal management of the air-cooled self-humidifying fuel cellare intercoupling. It is very crucial to control the optimal working temperature of the fuel cell, for keeping the water balance andthermal balance of the fuel cell, under a certain working current.Besides, it is also a key factor to affect the output performance ofthe fuel cell. Reference [8] proved by experiment tests that outputvoltage of the stack will gradually go up along with rising temperature at first, and when the temperature is up to a certain number,the output voltage will go down violently with the rising temperature. References [13–15] revealed by experiments that the optimalworking temperature really exists for the fuel cell, and when thestack is working in the range of the optimal temperature, its outputperformance is the best.