Discussion on traditional lithium battery charging methods

Different charging methods are important factors that affect the function and service life of single lithium batteries. Appropriate charging methods can not only maximize the capacity of the battery, but also extend the service life of the battery. This kind of influence mainly includes three aspects at present: (1) The influence of voltage. On the one hand, it is necessary to strictly control the battery voltage not to exceed the charge constraint voltage during the charging process. Exceeding the charge constraint voltage is called overcharge. Multiple times of slender overcharge will reduce the battery capacity and deform the battery. When the overcharge is severe, it will cause it to be straight. The battery exploded. On the other hand, after the charge is completed, the battery voltage should be as close as possible to the full charge voltage, otherwise the battery capacity will be greatly reduced. (2) The influence of electric current. The acceptable charging current of a lithium battery is limited. If the charging current is higher than this upper limit, it will cause the electrolyte in the battery to undergo gassing reaction, a lot of heat will be generated, and the battery temperature will rise sharply. (3) The influence of temperature. If the temperature of the lithium battery is too high, it will cause a series of reactions inside the battery, and the battery may explode. Therefore, during the charging process, the battery temperature should be monitored and controlled in time. Choosing a suitable charging method can increase the charging power in the past and extend the service life. There are many ways to charge lithium batteries. Commonly used charging methods include stable current charging method, stable voltage charging method, constant current/constant voltage charging method, variable current charging method, pulse charging method, intermittent charging method, etc. 1.1 The stable voltage charging method The stable voltage charging method refers to charging the battery with a stable voltage 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 charging loop resistance). In the initial stage of charging, because the battery potential is low, the charging current is relatively large. As the charging progresses, the battery potential gradually increases and the charging current gradually decreases. The constant voltage control system structure is simple, and the charging current is relatively close to the acceptable charging current, which has certain adaptability, but the current is relatively large in the initial stage of charging, which may cause the battery temperature to rise too fast, which will have an unlucky effect on the battery. 1.2 The stable current charging method The stable current charging method refers to charging with a stable and constant current throughout the charging process. The acceptable charging current of lithium batteries decreases exponentially with the charging time, while the charging current stays the same. If the charging current is large, the charging current may exceed the acceptable current in the later stage of constant current charging, causing the battery electrolyte to undergo gassing reaction , But if the charging current is too small, the charging time will be extended and the charging power will be reduced. 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 post: What is the cause of the zero voltage or low voltage of the polymer lithium battery?