Optimizing PCM-fin structure Li-ion battery thermal management system under mechanical vibrational condition: a comparative study

The thermal management method combining Phase Change Material (PCM) and metal fins has become a highly efficient and promising cooling method for lithium-ion battery (LIB), which is currently a hot research topic. However, the working environment of the Battery Thermal Management System (BTMS) for electric vehicles inevitably involves mechanical vibrations, which have been neglected in previous studies on PCM-fin structure BTMS. This research is the first to look into the effect of mechanical vibrations on the thermal performance of PCM-fin structure BTMS and compare it with the thermal performance of the BTMS under non-vibration condition. The outcomes indicated that the presence of mechanical vibration affects the optimal parameters of the fin structure in the PCM-fin structure BTMS. Compared with the case of the BTMS with optimal fin parameters under non-vibration condition, under vibration condition with an amplitude of 30 mm and a frequency of 30 Hz, it is possible to reduce the weight of the BTMS by 5.67% while further reducing the highest LIB temperature by 0.55 K and achieving a more uniform temperature distribution. This is an important finding that mechanical vibration is a critical factor that must be taken into account during the design of the BTMS fin parameters and has a dramatically positive effect on the lightweight optimization of the BTMS. This research can act as a guide for the practical engineering application of PCM-fin structure BTMS and promote the development of lightweight electric vehicles.