Investigation of the Liquid Cooling and Heating of a Lithium-Ion Battery Package for an Electric Vehicle

The temperature of an electric vehicle battery system influences its performance and usage life. In order to prolong the lifecycle of power batteries and improve the safety of electric vehicles, this paper designs a liquid cooling and heating device for the battery package. On the device designed, we carry out liquid cooling experiments and preheating experiments. Then, a three-dimensional numerical model for the battery package is built, and its effectiveness is validated by comparing the simulation results with the experimental outcomes in terms of battery surface temperature and temperature difference. Furthermore, we investigate the influences of the liquid flow rate and the inlet temperature on the maximum temperature and temperature difference of batteries by the cooling models and preheating models. Results show that: at the cooling stage, it is able to keep each battery working at an optimal temperature under different discharge conditions by changing the flow and the inlet temperature of liquid; at the heating stage, large flow rates and high inlet temperatures are able to speed up the preheating process, thereby saving time of the drivers.