Which factors affect the performance of lithium batteries?

There are many factors that affect the capacity of lithium batteries, such as operating temperature, charge and discharge current, charge and discharge cut-off voltage and other factors will affect the rate of degradation of lithium batteries. The mechanism that causes the capacity decline of lithium batteries can be divided into three categories: internal resistance and polarization increase, positive and negative active material loss, and Li loss. Different external factors have different effects on these three. For example, lithium batteries made of LiFePO4 material have very good cycle performance, but different use conditions have an important impact on the cycle life of lithium batteries. Experiments have proved that 15C pulse discharge and 15C continuous discharge are performed on 26650 lithium batteries. The two discharge systems have completely different effects on 26650 lithium batteries. The 26650 lithium battery with 15C pulse discharge has a very fast capacity decline. After 40 cycles of charging and discharging, 15C discharge can no longer be performed, but 1C discharge can still be performed. The 15C continuous discharge battery capacity decays slowly. After 60 times, the 15C discharge can still be performed, but the decay rate of the 1C rate is faster than the 15C pulse discharge. Lithium battery production customized lithium battery charging strategy research on the impact of lithium battery life decay can better direct our design of lithium batteries. The following different charge control strategies affect the life decay of lithium batteries, the usage mechanism is studied, and the life decay model of lithium batteries is proposed. The mechanism is broken down to the conclusion: 15C pulsed batteries have more LiF in the SEI film of the negative electrode, and LiF hinders the diffusion of lithium ions more, which makes the Li+ diffusion resistance and charge exchange resistance of the battery increase rapidly, thus making The polarization voltage of the battery is too large during the charging and discharging process, which leads to the rapid decline of LiFePO4 high current discharge capacity. 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: 18650 lithium battery pack capacity measurement steps and advantages analysis