Cooling capacity of a novel modular liquid-cooled battery thermal management system for cylindrical lithium ion batteries

Effective battery thermal management system (BTMS) is significant for electric vehicle to maintain the properties and life-time of the battery packs. As an effective cooling method, liquid cooling appears in many publications, but the study of cooling performance based on practical modular structure is relatively scarce. This paper has proposed a novel modular liquid-cooled system for batteries and carried out the numerical simulation and experiment to study the effect of coolant flow rate and cooling mode (Serial cooling and parallel cooling) on the thermal behavior of the battery module. The results show that increasing the coolant flow rate can significantly lower the maximum temperature and improve the temperature uniformity of the battery module in a certain flow range; when the flow rate increases to a certain value, increasing the cooling water flow rate has no obvious effect on improving cooling effect. Compared with serial cooling, parallel cooling can evidently promote the temperature uniformity of the battery module. Furthermore, the designed flow direction layout III can control Tmax to 35.74 °C with ΔT as 4.17 °C. The modular structure can be suitable for industrial batch production and group the batteries flexibly to meet the actual demand. The present study can provide a new approach for the modular design of liquid-cooled battery thermal management system.