Thermal Efficacy of a Li-Ion Battery Pack: The Effects of Different BTMS Setups
摘要
The aim of this work is to conduct a numerical analysis on a battery thermal management system (BTMS) that utilizes liquid cooling and is equipped with a cold plate. The system is specifically designed for a 2 × 6 format of a 18650 cylindrical Li-ion battery pack (BP). In order to analyze cooling performance of the BTMS, three distinct cold plate setups of the BTMS and varying volume flow rates (0, 0.1, 0.25, 0.5, 0.75, and 1 l/min) are utilized at a fixed discharge rate of 2C. The initial setup, denoted as Setup I, pertains to the implementation of symmetrical cooling. The subsequent setup, referred as Setup II, involves the utilization of asymmetrical cooling. Lastly, the third setup, designated as Setup III, encompasses both asymmetrical cooling and the incorporation of an aluminum block. Numerical analyses are performed with the ANSYS Fluent software. The study involves comparing of these setups in terms of the pressure drop throughout the cold plate, the greatest temperature difference between the cells, the hot spot temperature within the BP, the cooling efficacy as well as the energy density of the BP. The findings indicate that there is a negative correlation between flow rate and both hot spot temperature and the greatest temperature difference within the BP. Nevertheless, once the flow rate reaches 0.5 l/min, any subsequent increase in flow rate does not appear to significantly impact the cooling performance. Furthermore, it is observed that the pressure drop exhibits a positive correlation with the flow rate. Hence, it can be concluded that flow rates ranging from 0.25 to 0.5 l/min are seen to be the most favorable for these BTMS setups. When comparing the BTMS setups, it can be concluded that Setup III is the optimal setup, particularly when considering factors such as the hot spot temperature and the greatest temperature difference within the BP.