Optimization Design Of Cooling Scheme On Lithium Ion Batteries For Vehicles

As the energy decreases and pollution increases, electric vehicle has become the country’s current development focus. As the the main source of power, battery performance is crucial to the development of electric vehicle industry. Battery operating temperature will directly affect their performance, life and reliability. Power battery at work will generate a lot of heat, and is easier to gather more heat when packed in the compact vehicle space; therefore the research of cooling methods is important to ensure that the operating temperature of the battery pack can be maintained within a reasonable range, as well as the temperature consistency.In this paper, the main contains are listed below:(1)The development advantages of electric vehicles, power battery development status and battery thermal management system is analyzed, and the main research method of battery thermal model is proposed.(2) The structure and working principle of lithium-ion battery is introduced, also the principle of heat and heat transfer characteristics. The best performance temperature range of lithium-ion battery is determined. Also, a basic heat transfer model of lithium-ion battery pack has been established. By Fluent software, a simulation is conducted to master the battery pack temperature distribution under natural convection conditions.(3) Simulations are conducted to compare the cooling capacity of ambient wind cooling, air conditioning wind cooling and heat transfer oil cooling methods,and the impact of the discharge rate, temperature and fluid velocity to the temperature field is mastered;(4) According to the data collected from real car running, the battery status of different vehicle operating conditions has been mastered, and an appropriate solution to optimize cooling is proposed.The results of this paper can be used as a reference of the further design of battery thermal management system..