Experimental and numerical study of PCM thermophysical parameters on lithium-ion battery thermal management

Lithium-ion battery (LIB) nowadays plays a key role as one of the most widely used energy storage technologies such as the application in electric vehicles. Thermal management critically affects the performance of LIB. Phase change cooling using phase change material (PCM) has become a promising method due to its high latent heat and no need to consume extra pump power. In this study, thermal performance of a battery module with 25-parallel 18650 lithium-ion battery has been numerically and experimentally investigated by adopting phase change cooling with PCM. Firstly, the internal resistance of the unit cell has been experimentally tested to build up the heat generation model. Based on the heat generation model and heat transfer model, the effects of PCMs thermophysical parameters including thermal conductivity, latent heat and porosity are investigated when they are applied in the thermal management of designed LIB module. The results indicate that the higher thermal conductivity and latent heat lead to better thermal management performance comprehensively considering the maximum temperature and temperature uniformity of LIB module. Results also illustrate that thermal management performance increases very slightly when the thermal conductivity and latent heat attain a relatively high value. As for the porosity of paraffin/metal foam, an optimal value of 94% exists to achieve the lowest maximum temperature for LIB module.