Effect of Battery Thermal Management System on Temperature Distribution and Uniformity

Abstract

Thermal runaway is an essential problem to be solved urgently for electric vehicles, and the safety issues have attracted the attention of researchers. Proper thermal management systems can effectively reduce the surface temperature of battery pack and improve the uniformity of the temperature distribution, which can effectively prevent the occurrence of thermal runaway phenomenon. This paper takes the large-capacity square-shell lithium-ion battery as the research object, and conducts in-depth research on its heat production under different working conditions through simulation. A hybrid battery thermal management system based on heat pipes, microchannel liquid-cooled plates, and phase-change materials was established, and the thermal management performance under world light vehicle test cycle conditions was studied. The results indicated the temperature evolution of each battery tended to be consistent in the first 1,500 s. In the subsequent process, the discharge rate of the battery was positively correlated with the speed of the vehicle and therefore brings the corresponding temperature response. During world light vehicle test cycle, the maximum temperature difference of the lithium battery module was 3.5 K. At the end of the test, the average temperature difference of the lithium-ion battery module was 3.2 K.