Analysis of the Thermal Characteristics and Thermal Management of Lithium-ion Power Battery

The heat generation mechanism of lithium-ion power battery was analyzed. It was concluded that the battery heating was related to the temperature coefficient of electro motive force, the SOC of the battery, the resistance of the battery, the current ratio . Based on the experiment, the important characteristic of the NCM were studied at different ambient temperatures. Experimental results are as follows. The discharge capacity increases with the increase of ambient temperature, and decreases with the increase of discharge ratio. The battery resistance rises obviously at low temperature, and discharge resistance is greater than the charging resistance. The SOC-OCV curve in the low temperature is lower than in the high temperature. The discharge efficiency curve gave the temperature reference range for normal operation of the battery. The study provides an important basis for the technology progress of battery thermal management technology for electric vehicles.