Abstract
To maintain optimal operating temperatures for lithium-ion batteries under extreme operating conditions, a battery thermal management system (BTMS) integrating the thermoelectric cooler (TEC), liquid cooling, and composite phase change material (CPCM) is developed. Moreover, a transient numerical model has been established, considering thermal, electrical, and fluid multiphysics fields, to precise evaluation the system's performance. The outcomes indicate a decrease in both the maximum battery temperature and CPCM liquid fraction as the expanded graphite (EG) mass fraction, TEC cooling input current, and coolant flow speed increase. Furthermore, the temperature difference among batteries exhibits a decrease as the EG mass fraction increases, but experiences an elevation with an increase in both current and coolant flow speed. The BTMS features the lowest power consumption and optimal cooling performance at the EG mass fraction of 12 %, the TEC cooling input current of 3 A, and the coolant flow speed of 0.05 m/s. In preheating situations, the battery pack can achieve a temperature of 293.15 K starting from 263.15 K with the assistance of TEC preheating input currents of 4 A and 5 A, taking 5600 s and 2240 s, respectively, to complete the entire preheating procedure. This study will offer new insights into the advancement of the BTMS, allowing for the control of battery temperatures in high-temperature and high-discharge rate conditions, coupled with preheating at low-temperature.
•A novel BTMS combined with thermoelectric coolers and phase change materials is proposed.•A transient thermal-electrical-fluid multi-physical field numerical model is developed.•The novel BTMS features both high-temperature cooling and low-temperature preheating functions.•Effect of various parameters on the thermal performance of the BTMS is studied.