Explain the impact of connector temperature rise on the energy storage performance of lithium batteries

In the lithium battery energy storage system, the temperature sensitivity of the lithium battery is mainly due to the temperature sensitivity of the material's physical and chemical properties. Temperature will directly affect the activity and conductivity of the electrode material, the insertion and deintercalation of lithium ions on the electrode, the lithium ion permeability of the separator, etc., and then affect the electrochemical reaction inside the battery, and its external performance is a power lithium ion battery Temperature sensitivity. When the lithium battery continues to work above 45°C, its cycle life is clearly reduced, which is more obvious when charging and discharging at high rates. Therefore, if you work in a high temperature environment for a long time, the life of the power lithium-ion battery will be clearly shortened, and its performance will be greatly reduced, and even cause safety accidents. Similarly, if the temperature is too low, the activity of the active materials inside the battery will be significantly reduced, and the internal group and polarization voltage will increase, and the charge and discharge power and capacity will be significantly reduced, and even cause the irreversible degradation of the lithium battery capacity, and buried safety hazards. In addition, the long-term uneven distribution of the temperature field inside the lithium battery box will also cause the imbalance of the performance of each battery module and cell, especially the aging rate of the battery distributed in the high temperature area will be significantly faster than the low temperature part, as time goes by Accumulated differences in physical properties between different batteries will become more distinct, resulting in poor consistency between lithium batteries, and even premature failure, shortening the life of the entire power lithium-ion battery system. The connector is a necessary element for series and parallel connection between lithium battery packs. When the battery pack is charged and discharged, the passing of a large current will cause the connector to have a thermal effect. When the temperature of the connector rises and exceeds the temperature of the lithium battery pack, the temperature is It will spread to the inside of the battery, which will affect the stability of the battery. Therefore, it is a necessary condition for the connector to achieve low temperature rise characteristics. The dedicated energy storage connector keeps the contact surface between the terminal and the pin in the best area, effectively reducing contact Resistance reduces overcurrent density and current temperature rise; at the same time, multiple surfaces are designed into corrugated sectors to improve the heat dissipation function. In addition, the metal material adopts imported high-purity copper, which has high electrical conductivity and stable overcurrent temperature rise. The plastic material uses a unique alloy material, which integrates a variety of plastic characteristics, combines high strength and high toughness, and meets fire protection requirements at the same time. It has a high thermal conductivity and speeds up heat dissipation. In terms of the connection technology between the internal terminals and the wire nose, the FIRST patented technology is used to ensure the reliability of the connection between the two, increase the contact area, and effectively reduce the overcurrent temperature rise. At the same time, The stable and firm multi-point crimping process effectively reduces the temperature rise of the connection between the wire nose and the wire, and ensures the consistency of the temperature rise of the lithium battery. Low temperature rise design is an inevitable trend in the development of connectors: currently in the field of energy storage, the use and development of lithium batteries are very rapid. Lithium battery energy storage has the advantages of high energy density, long service life, and environmental protection, but there are also some disadvantages. , The processing cost is high, the safety performance is poor, and there is a danger of explosion. Therefore, the safety design of the thermal management system is crucial for the use of lithium batteries. The connector is an indispensable component between the battery pack in series and parallel. The temperature rise effect has a great impact on the entire lithium battery energy storage system, so the low temperature rise design has become an inevitable trend in the development of connectors. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Why do ETC backup UPS power supplies use lithium iron phosphate batteries?