Temperature characterization analysis of LiFePO~4/C power battery during charging and discharging

摘要

In order to study the surface temperature change and distribution during charging and discharging and in the simulation working condition of LiFePO _4/C power battery at normal temperature, the surface temperature is tested by placing the battery in the incubator and fixing 10 temperature probes on the battery surface. Results show that the temperature of the upper part is higher, and the temperature at the bottom is the lowest, while around the positive electrode is the highest during charging and discharging. The maximum temperature rising rate is reached at the moment of constant current charging transforming to the constant voltage charging during charging, and at the end moment during discharging. During charging in a certain range and discharging, the relations between the maximum temperature, the average temperature rising rate, and the maximum temperature difference of all the measurement points at the same time and the current are approximately linear, respectively. In the simulation working condition, the moment of the maximum temperature is consistent with the large current discharging instantaneous in each stage.