Optimization of battery thermal management system based on phase change materials coupled with immersion cooling

Composite battery thermal management can effectively leverage the strengths and weaknesses of individual thermal management methods to significantly enhance their performance. In this paper, a novel composite battery thermal management method based on phase change materials (PCMs) and oil immersion cooling is proposed, and their cooling performances are thoroughly compared with the individual system with air, PCM, and transformer oil in terms of cycle rate and phase change temperature (PCT). It is found that the composite cooling system exhibits superior cooling performance for all the experimental configurations. For composite systems based on different PCMs with PCTs of 37 degrees C and 58 degrees C (denoted as MIX-37 and MIX-58), the MIX-37 system shows lower battery temperature and better temperature homogeneity at lower battery cycle rate because of its higher latent heat utilization rate, while PCM-58 mainly works in the form of sensible heat in the MIX-58 cooling system to accelerate cooling efficiency with the increase of cycle rate.