Because the temperature is too high or too low will directly affect the service life and performance of the power lithium battery, and may cause the safety of the battery system, and the long-term uneven distribution of the temperature field in the battery box will cause the battery modules and cells. The performance is not balanced, therefore, the battery thermal management system is necessary for the power lithium battery system of electric vehicles. A reliable and efficient thermal management system is of great significance to the reliable and safe application of electric vehicles.

The battery pack thermal management system has the following 5 important functions:

①Accurate measurement and monitoring of battery temperature.

② Effective heat dissipation and ventilation when the battery pack temperature is too high.

③Rapid heating under low temperature conditions.

④ Effective ventilation when harmful gases appear.

⑤Ensure the uniform distribution of the temperature field of the battery pack.