What kinds of cooling methods are commonly used in proton exchange membrane fuel cells include

1. Liquid Cooling: Liquid cooling is a common cooling method, which absorbs the heat generated by the fuel cell through circulating coolant (water or glycol aqueous solution). The coolant circulates between the fuel cell stack and the heat sink to take away the heat through heat exchange and keep the temperature of the fuel cell within a controlled range.

2. Phase Change Cooling: Phase change cooling utilizes the property of liquid releasing or absorbing a large amount of heat in the process of phase change to cool the fuel cell. Using liquids with high boiling point (such as Freon or ammonia) as coolant, when the fuel cell generates heat, the coolant will undergo phase change to absorb heat and keep the temperature of the fuel cell stable.

3. Air cooling: Air cooling is a simplified cooling method that utilizes convection and heat dissipation of the surrounding air to reduce the temperature of the fuel cell. The surface of the fuel cell stack is designed to have good heat dissipation performance, and the cooling effect is realized by transferring the heat to the surrounding air with the help of natural convection or auxiliary fan.