At present, the main method of lithium ion polymer battery charging is the voltage and current limiting method. In the initial stage of constant current (CC) charging, the battery has the strongest acceptance ability. With the continuous charging process, the polarization effect is strengthened, the temperature rise is intensified, and the voltage rises. When the charge reaches about 70 ~ 80%, the voltage reaches the maximum charging limit voltage, and the battery is transferred to the constant voltage (CV) charging stage. In the constant voltage stage, it is called trickle charging. It takes about 30% of the time to charge 10% of the electricity. The current intensity decreases and the temperature rise does not increase.

    In this process, the total voltage or average voltage control of the battery pack is considered. In fact, the battery with a higher single voltage has entered the overcharge stage relative to other batteries in the pack. Similarly, when discharging, there are over-discharged batteries in the group. Overcharge and over-discharge are fatal to the battery. The only difference is that overcharge produces a lot of gas, which is easy to ignite and explode, and the appearance is violent; The appearance of over-discharge changes gently, but the failure rate is very fast. It should be strictly avoided in normal use.

    In this regard, there is a new lithium battery charging method called parallel control and balance management, which can manage the charge and discharge of each cell separately and balance control. This dynamic balance focuses on the advantages of discharge balance and charge balance, although there are differences in the initial capacity, voltage, and internal resistance between cells, In the work, it can ensure the consistency of relative charge and discharge intensity and depth, and gradually reach the common end of life. This method is especially suitable for high current discharge.

    Therefore, when charging the lithium battery, it is necessary to use a special lithium battery charger. In particular, it is necessary to pay attention to the matching and consistency of the parameters with the core used. When the lithium battery is used in combination, it is necessary to add a PCB protection board to the battery pack, so as to avoid the cell package, leakage, even fire, and explosion, so as to extend the service life of the battery as far as possible, but the battery can not be charged and discharged, Increase the number of battery cycles.