Numerical study of a novel battery thermal management system for a prismatic Li-ion battery module

The life time and performance of Li-ion batteries are significantly influenced by the operating temperature. In order to maintain performance and avoid temperature related degradation, the highest temperature of the batteries are required to be below 35^oC, and the temperature variation between batteries in a module needs to be less than 5^oC. These requirements are hardly to be satisfied by the traditional air cooling battery thermal management system (BTMS) in an extreme ambient condition of 40^oC. Therefore, a novel water cooling BTMS was proposed and numerically investigated for a module consisting of 15 prismatic lithium iron phosphate batteries at 1 C discharging rate. The results show that the average temperature of 34.5^oC and temperature difference within each battery less than 1.8^oC can be obtained if the water inlet temperature is 28^oC and the flow rate is 1 g/s. The average temperature variation between individual batteries in the module is less than 0.5^oC. The average battery temperature reduces as the water flow rate increases. However, the effect of the water flow rate on the battery temperature is far less significant than the water inlet temperature.