Providing implications for electric vehicle applications through experimental exploration on temperature distribution and heat flow for a high Ni content battery module thermal management system under multi-operating scenarios

Abstract

Recently, there has been an increase in accidents due to thermal runaway issues with the mass adoption of electric vehicles in China. Avoiding thermal runaway incidents has become an essential need for electric vehicle development. Controlling abnormal temperatures is a key scientific study in battery thermal safety research. Therefore, this study provides a comprehensive analysis of module temperature distribution in the high Ni content commercial lithium-ion battery module for electric vehicles by three experimental groups. The results of the tests show that the wrap-full insulation keeps heat and mitigates the temperature non-uniformity better, but the bottom-only insulation reduces temperature faster. Active cooling can reduce the non-working module temperature from 45 °C to 27 °C in 2160 s, but natural convection keeps the temperature at about 45 °C. Under complex operating, the maximum temperature difference of the module reaches 9–10 °C. After adding active cooling, the maximum temperature difference on the module is reduced by 1 °C, and the cooling speed is accelerated by 35 %. In short, a thermal gap exists between the total positive and negative and other, which is one of the primary causes of the large temperature difference within the module. The heat transfer direction inside the module is from the middle to the sides, but it is the opposite under natural cooling. We hope to provide a useful analysis of module temperature distribution that guides the cooling layout design/application.