Effect of thermal management system parameters on the temperature characteristics of the battery module

Abstract

In the present inquiry, a novel electric-thermal coupled model is devised to delve into the battery module's temperature distribution characteristics at different ambient temperatures and discharge rates. The accuracy of temperature prediction accuracy is contingent upon the experimental determination of the entropy heat coefficient and convective heat transfer coefficient. In the absence of a thermal management system for the battery module, an escalation in the discharge rate correlates with an increase in the average temperature, average temperature rise, and maximum temperature difference, while a decline in the initial ambient temperature relates to a decrease in these values. Under typical vehicle driving cycle conditions, the average temperature curves show peaks before the end of the cycle. The wider speed range, longer testing time, and reduced regularity of the driving cycles cause both the average temperature and maximum temperature difference to increase. Further research is done into the effects of coolant flow rate and temperature, and contact thermal resistance on the efficiency of thermal management systems. Gradual decrease in the average temperature transpires as the coolant flow rate increases, but excessively high flow rates engender a larger maximum temperature difference. As the coolant temperature decreases, both the average and maximum temperature difference decrease, but temperature uniformity is worsened. The average and maximum temperature difference generally rise when the thermal contact resistance increases, and a low thermal contact resistance leads to a more uniform low-temperature distribution.