How to improve the high-rate performance of lithium batteries?

What are the ways to improve the high-rate performance of lithium batteries? ①Material selection Generally speaking, it is important to improve the rate performance of power lithium batteries. It is important to start with the selection of materials. At a normal temperature of 20℃, the minimum electronic conductivity of LCO materials is only 5x10-8S/cm, while the electronic conductivity of NCM111 materials can reach 2.2. x10-6S/cm, with the further increase of the nickel content, the electronic conductivity of the ternary material has also increased significantly, and the electronic conductivity of the NCM8111 material has reached 4.1x10-3S/cm, and the ionic conductivity also shows the same The ionic conductivity of LCO material is only 2.3x10-7S/cm at 20℃, while the ionic conductivity of NCM111 material is 3.2x10-6S/cm, NCM532 is 1.7x10-3S/cm, and NCM622 is 3.4x10- 3S/cm, NCM811 material has reached 6.3x10-3S/cm. ②Formulation optimization determines the rate performance of lithium batteries. Another key to the battery formulation design. There are two types of conduction in lithium batteries, ion conduction and electronic conduction. Among them, ion conduction mainly includes Li+ in the electrolyte, the internal pores of the electrode and the internal active material. The diffusion of electrons is important for the conduction between active material particles. ③The choice of battery structure is also a very important issue about how to control the temperature of the rate battery during the discharge process. During the high current discharge process, the lithium battery will produce a lot of heat, and the accumulation of heat inside the lithium battery will cause the temperature to rise. , There is a large temperature gradient, so the inconsistency of the internal decay of the lithium battery affects the life of the lithium battery. How to choose an appropriate structure becomes particularly important. ④Improve the ionic conductivity of the electrolyte. Lithium ions need to shuttle back and forth between the positive and negative electrodes, just like swimming in a swimming pool formed by the electrolyte and the battery case. The ionic conductivity of the electrolyte is the same as the resistance of water. Speed u200bu200bhas a very big impact. At present, the ionic conductivity of organic electrolytes used in lithium batteries, whether liquid electrolytes or solid electrolytes, is not very high. The resistance of the electrolyte has become an important part of the overall battery resistance, and its impact on the high-rate performance of lithium batteries cannot be ignored. 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: How to solve the safety of lithium iron phosphate batteries?