Investigation of multifactorial effects on the thermal performance of battery pack inserted with multi-layer phase change materials

The safe and efficient power battery thermal management system (BTMS) is a prerequisite for the effectiveness and long service life of electric vehicles. So, a BTMS with inserted multi-layer phase change materials (PCMs) is proposed to enhance the safety and working performance of battery pack. Effects of PCM settings and operating conditions on the thermal performance of battery pack are discussed and analyzed. The results reveal that PCM cooling plays a significant role in the thermal management of battery pack, where the maximum temperature value and temperature difference of BTMS with multi-layer PCM #C are respectively reduced by 13.61 °C and 2.54 °C compared to battery pack without PCM. Besides, the coupling effects of multiple factors, that is, PCM permutation, the thickness and height of PCMs, and ambient temperature, on the heat dissipation of battery pack are discussed via orthogonal results analysis. The optimized multi-layer PCMs are obtained for the BTMS, i.e., Ps = 121, h1 = 5 mm and L = 6 mm, which achieves the lowest values of Tmax = 43.02 °C and ΔT = 3.37 °C at Tamb = 20 °C. It provides insights for optimizing thermal control strategies for the advancement of thermal management in electric vehicles, ultimately enhancing safety, performance, and longevity.