Detailed explanation of battery thermal management system

Temperature has a great influence on battery life. For the same battery cell, at an ambient temperature of 23°C, the remaining capacity of the battery after 6238 days is 80%, but the remaining capacity of the battery after 272 days in an environment of 55°C has reached 80%. The temperature rises by 32℃, the life of the battery cell is reduced by more than 95%, so the temperature has a great influence on the life, the higher the temperature, the more serious the life decline. 1. The appearance of battery heat: due to the existence of battery impedance, during the charging and discharging process of the battery, the current flows through the battery to cause heat to appear inside the battery. In addition, the electrochemical reaction inside the battery will also cause a certain amount of heat generation. 2. The impact of temperature rise on battery life: The increase in temperature has an impact on the calendar life and cycle life of the battery. 3. Too low or high temperature will affect the performance and service life of the lithium battery, so it is necessary to have a thermal management system. According to different heat transfer media, battery thermal management systems can be divided into air-cooled, direct-cooled and liquid-cooled. Liquid-cooled is cheaper than direct-cooled, and the cooling effect is better than air-cooled, which has a mainstream use trend. The battery powers the motor and the motor drives the load. The heat generated by the battery is exchanged between the coolant and the refrigerant through the heat exchanger between the liquid cooling cycle and the air-conditioning system, and then is transferred to the engine compartment through the air-conditioning system, and finally the heat is transferred to the engine compartment. The air takes away. The key functions of battery thermal management include: accurate measurement and monitoring of battery temperature; effective heat dissipation when the battery pack temperature is too high; rapid heating under low temperature conditions; ensuring the even distribution of the battery pack temperature field; match. The temperature of the battery directly affects the safety of the battery, so the design and research of the thermal management system of the battery is one of the most critical tasks in the design of the battery system. Must strictly follow the battery thermal management design process, battery thermal management system and component types, thermal management system component selection and thermal management system performance evaluation and other aspects to carry out the battery system thermal management design and verification, In order to ensure the performance and safety of the battery. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete it. Previous post: How long will it take for the all-solid-state lithium battery to be marketed?