Thermal characteristics of power battery pack with liquid-based thermal management

• Published in: Applied thermal engineering 2020-01, Vol.164, p.114421, Article 114421
• Main Authors: Liu, Jinwei, Li, Hao, Li, Wangyong, Shi, Junye, Wang, Huihui, Chen, Jiangping
• Format: Article
• Language: English
• Subjects: Ambient temperature; Batteries; Charge-discharge ratio; Charging; Cooling; Electric vehicles; Energy management; Energy storage; Heat capacitance; Heat source; Heat transfer; Liquid-based battery thermal management; Lithium-ion batteries; Product safety; Rechargeable batteries; Storage capacity; Temperature uniformity; Thermal energy; Thermal management
• ISSN: 1359-4311; 1873-5606
• DOI: 10.1016/j.applthermaleng.2019.114421

•The impacts of material heat capacity, environmental temperature, charge-discharge rate, and heat source type on battery thermal parameters are explored from a macro perspective of power battery pack.•Extending the cooling time by 5 min at the end of discharging is essential, since a large amount of heat will be generated when a discharge is coming to an end or just finished.•Under the same charge and discharge rate, the battery generates more heat during the charging process than the discharge process.•The overall temperature uniformity of the power battery is better under the higher ambient temperature, Therefore, in a hot area, the life of power battery of EVs may be longer.•Thermal management on a single surface definitely fails to ensure uniform temperature on all surfaces of PBP. Thus, immersion cooling may be a better choice for BTMS in the future. Thermal management of a battery system is critical for maintaining energy storage capacity, driving range, cell longevity and safety, while lithium-ion battery electric vehicles are becoming increasingly popular. Thermal management studies at battery pack level have a practical guiding significance for the exploration of appropriate battery thermal management schemes and strategies, which are seldom taken into account in the study of liquid-based battery thermal management system (BTMS). The effects of heat capacitance, heat source characteristics, ambient temperature and charge-discharge ratio on the thermal performance of liquid-based BTMS are experimentally investigated in this study. The results indicate that active battery thermal management should be adopted, and self-discharge heating might be an appropriate way to warm up power battery pack uniformly. In the charging and discharging process of the battery, the temperature uniformity of the battery at 45 °C is better than that at 25 °C. What’s more, during charging and near the end of discharging, the cell generates a tremendous amount of heat, in which case, cooling measurement should be enhanced and cooling should be maintained for 5 min at least after the end of charging.