Effect analysis on thermal behavior enhancement of lithium-ion battery pack with different cooling structures

Thermal management plays a vital role in ensuring that each single cell in the battery pack works within a reasonable temperature range while maintaining the temperature uniformity among the cells and battery modules in the pack as much as possible. In this study, an electrochemical-thermal model coupled to conjugate heat transfer and fluid dynamics simulations is utilized to accurately evaluate the thermal behavior of the battery pack. The effect of different cooling structures, the number of mini-channels, and the inlet mass flow rate on the temperature indexes of the battery pack are investigated by single-factor analysis method. Then, the simple and efficient orthogonal analysis and comprehensive analysis are used to obtain the optimal factor combination. Results show that the cooling structure design significantly affects the area where the highest temperature occurs in the battery pack. Meanwhile, case D can obviously improve the temperature indexes of the battery pack. The maximum temperature of the battery pack decreases as the number of mini-channels increases, but the downward trend decreases. On the basis of aforementioned work, the optimal combination can control the maximum temperature below 302 K and reduce the maximum temperature difference to 3.52 K. The research and optimization strategies in this paper can provide promising optimization solutions for battery thermal management systems.