Thermal management system for lithium-ion batteries based on the coupling of multi-layer composite phase change materials and liquid cooling
摘要
Lithium-ion batteries play a crucial role in electric vehicles (EVs) owing to their high energy density and long cycle life. However, maintaining their operating temperature within the optimal range requires advanced battery thermal management systems (BTMS) to meet the ever-evolving performance requirements of EVs. The purpose of this study is to effectively integrate liquid cooling with composite phase change material (CPCM) cooling and to enhance the contribution of the heat transfer performance of phase change materials to BTMS efficiency by adopting an innovative multilayer phase change material structure. To better analyze the characteristics of water flow direction, cooling plate width, inlet flow rate, CPCM doping ratio, multilayer CPCM structure, and battery pack temperature distribution in the composite thermal management system, the charging and discharging thermal behaviors of the battery were simulated and verified. The results indicate that the BTMS proposed in this study can significantly improve the temperature field distribution within the battery pack. Specifically, under an ambient temperature of 298.15 K, a water flow rate of 1 L min−1 and a 2C discharge rate, the BTMS based on multilayer CPCM coupling can reduce the maximum internal temperature of the battery pack to 303.93 K, with a maximum temperature difference of only 1.1 K. Compared with the scenario without cooling, the maximum temperature is reduced by 27.02 K, and the maximum temperature difference is reduced by 8.1 K. This study provides an efficient solution for the design and optimization of BTMS in EV lithium-ion batteries.