Design and Analysis of Battery Box Based on Graphite-Phase Change Material and Air Cooling

摘要

Cooling performance of battery box is a key factor to ensure EVs safe driving. By comparing the advantages and disadvantages of various current heat dissipation methods, the composite cooling mode based on air cooling mode and heat dissipation mode of phase change material is selected. The battery box is made up of battery cells with aluminum plate as skeleton with processing and welding, the heat dissipation part is mainly composed of paraffin, graphite and copper tubes. Then, the simulation analysis is carried out in ANSYS to obtain the heat dissipation characteristics of the battery cell, at the same time, the temperature distribution and flow field distribution of the battery pack under different cooling wind speeds are also obtained. The local structure adjustment of the battery box is carried out according to the simulation results. Finally, the battery cooling box is used for experiment test. Under the conditions of 4A discharge current and 1C rate discharge current, four heat dissipation experiments were carried out, namely PCM discharge temperature test, AC (air cooling) discharge test, PCM and AC discharge test, and NC (natural cooling) discharge test. After the PCM board is installed at both ends of the battery pack and the internal shape optimization of the cooling fan mounting groove, the results show that the heat dissipation characteristics of the battery are significantly improved to meet the normal working conditions of the battery.