A battery thermal management scheme suited for cold regions based on PCM and aerogel: Demonstration of performance and availability

Abstract

The temperature of lithium-ion batteries affects their safety, operation efficiency and life. In a cold environment, the battery system may have the problem of low temperature. To solve this problem, this work has established a battery thermal management system (BTMS) for public transport batteries, which uses phase change material (PCM) and aerogels. PCM can store the heat generated by the battery through latent heat, and aerogel can maintain the temperature of the battery system through excellent thermal insulation and avoid the impact of low ambient temperature. First, according to the thermal conductivity characteristics of lithium-ion batteries, the optimal PCM distribution for a single battery is determined. The BTMS is designed according to the optimal distribution. Second, the effects of PCM thermal conductivity and aerogel thickness on the temperature variation of the BTMS under design conditions are investigated. Finally, the external environment parameters of Beijing in January are introduced to evaluate the availability of BTMS. The results show that PCM is optimal at 5.3 mm in the cell thickness direction. Increasing PCM thermal conductivity can reduce the demand for the thickness of the aerogel layer and the maximum temperature of the battery. During the whole operation of the BTMS in Beijing in January, the battery temperature can be maintained in the range of 20∼28 °C, and the maximum temperature difference is less than 2.6 °C. This work provides valuable information for designing the BTMS of batteries used for public transport in cold environments.