Development of thermal equivalent circuit model of heat pipe-based thermal management system for a battery module with cylindrical cells

The temperature prediction of a battery pack under various working conditions is one of the premise tasks for efficient thermal management. A heat pipe-based thermal management system is proposed for a battery module with cylindrical cells. Compared with the natural cooling, the temperature of the battery can be significantly reduced by about 14 degrees C in the 5 C discharge rate. A thermal equivalent circuit model (TECM) is developed to describe the thermal behavior of the battery module. In the model, the thermal behavior is in analogy with the electrical behavior. The TECM is experimentally validated under different discharge rates, coolant flow rates and inlet coolant temperatures. The temperature responses of nine key measuring points obtained from TECM has a good agreement with those from experiment and the maximum deviation is below 5%. The TECM has potential usefulness in the real-time prediction of temperature, analysis of large battery pack and development of control strategy.