Analyze the causes of aging of lithium-ion batteries

Causes of aging of lithium-ion batteries Aging generally refers to the placement of the battery after the first charge after assembly. It can be room temperature aging or high temperature aging. All functions are for the performance and composition of the SEI film formed after the initial charge. stable. The aging temperature at room temperature is 25°C, and high-temperature aging plants are different, some are 38°C and 45°C. There are two cases of aging between 48 and 72 hours and separate sealing: Regarding the battery that forms the opening, the relative humidity is controlled below 2% at room temperature, and the sealing effect is better after aging. Regarding high temperature aging, the sealing aging effect is better. But what is certain is that there are electrochemical dynamic changes during the aging process, which is of great help to the stability of the SEI and can promote the stability of the electrochemical system. The purpose of aging is actually the principle. One of the reasons is to fully infiltrate the electrolyte, and the other is that certain active components of the living cathode material can make the performance of the entire battery more stable through certain deactivation reactions. The process is faster. High temperature aging is used. High temperature aging should pay attention to the control time and temperature. However, due to high temperature aging, the degradation effect of living substances exceeding the normal temperature aging can occur. It is well controlled and the effective ingredients are fully reflected. The battery characteristics are stable and the control is not Good, so the electrical performance is reduced, the output is low, the addition of infrared, even leakage and other conditions are very likely to make the battery performance more stable after high temperature aging. In the production process of most lithium-ion battery manufacturers, high-temperature aging operations are used. The temperature is 45~50℃, and the battery ages for 1~3 days. After high-temperature aging, the potential undesirable phenomena of the battery will be exposed: voltage changes, thickness changes, internal resistance changes, etc. are all comprehensive indicators for directly testing the safety and electrochemical performance of this batch of batteries. At present, most battery companies use domestic inferior separators for mass production. High temperature aging has also become an unwritten rule for safety testing of the internal structure of the battery. High temperature aging is only to shorten the entire production cycle of the battery. Players entering the battery can only accelerate the chemical reaction at high temperature. The battery is not more than the benefits that may damage the battery, it is best to incubate at room temperature for more than three weeks, we are negative, the separator, sufficient electrolyte balance and other chemical reactions, and then the battery performance is more realistic. This is usually the case with lithium-ion batteries, because they have a limited number of charging and discharging times, so you should try to fully charge the phone’s battery. But I found an experimental table about the charge and discharge cycle of lithium-ion batteries. The data about the cycle life is as follows: Cycle life: 10%DOD>1000 times, 100%DOD cycle life:>200 times, where DOD is the abbreviation of depth of discharge . It can be seen from the table that the chargeable time is related to the depth of discharge, and the cycle life of 10% DOD is much longer than that of 100% DOD. Of course, if it is reduced to the actual total charging capacity: 10%*1000u003d100, 100%*200u003d200. The latter is still relatively good to fully charge and discharge, but in front of netizens, make some corrections: Under normal circumstances, you should have an appointment. According to the principle, the remaining battery power is used up before charging, but if your battery is in your expectation On the second day, it is impossible to persist throughout the day, and you should start charging in time. Of course, if you are willing to bring the charger to the office when you are BieLun again. 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. Previous article: The birth and principle of polymer lithium ion battery