Discuss the charging method of traditional lithium battery

Discuss the charging methods of traditional lithium batteries. Different charging methods are important factors that affect the function and service life of single lithium batteries. The correct charging method can not only maximize the battery capacity, but also extend the battery life. This kind of influence is mainly reflected in three aspects: (1) The influence of voltage. On the one hand, during the charging process, the battery voltage must be strictly controlled to prevent cross-charging bound voltage. The combined voltage across the charge is called overcharge. Repeated slight overcharge will reduce the battery capacity, deform the battery, and explode when severely overcharged. On the other hand, after charging, the battery voltage should be as close as possible to the full charge voltage, otherwise the battery capacity will drop significantly. (2) The influence of current. The acceptable charging current of lithium batteries is limited. When the charging current is higher than the upper limit, the electrolyte in the battery will undergo a gas extraction reaction, causing a lot of heat and the battery temperature will rise sharply. (3) The influence of temperature. The temperature of the lithium battery is too high, which will cause a series of reactions in the battery, and the battery may explode. Therefore, during the charging process, the temperature of the battery should be monitored and controlled. Choosing a suitable charging method can charge long distances and prolong the service life. There are many ways to charge lithium batteries, such as steady current charging method, constant current charging method, constant current/constant voltage charging method, variable current charging method, pulse charging method, intermittent charging method, etc. 1.1 Safe charging method Safe voltage charging method refers to the safe voltage charging of the battery during the charging process. In this process, the charging current satisfies the formula: Iu003d(UE)/R (where: I is the charging current, U is the charging voltage, E is the battery voltage, and R is the resistance of the charging circuit). At the beginning of charging, due to the low battery potential, the charging current is large. As the charging process progresses, the battery potential gradually increases and the charging current gradually decreases. The constant voltage control system has a simple structure, the charging current is close to the acceptable charging current, and it has a certain degree of adaptability. However, the relatively large current in the initial charging stage may cause the battery's temperature to rise too fast, which will adversely affect the battery. 1.2 Constant current charging method The steady current charging method refers to the use of steady current charging during the entire charging process. The acceptable charging current for lithium battery charging decreases exponentially with time, and the charging current does not change. If the charging current is large, the battery electrolyte analysis gas reaction caused by the charging current at the acceptable current may occur in the later stage of constant current charging, but if the charging current If it is too small, it will extend the charging time and charge the power source. The above two methods are relatively simple, but there are many shortcomings. The current is too large at the initial stage of constant voltage charging, and the current is too large at the later stage of constant current charging. Therefore, the charging method of constant current first and then constant voltage can be selected to overcome the shortcomings of these two stages. 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 article: Briefly describe the explosion conditions of large-capacity polymer batteries and battery protection methods