What are the equalization methods for lithium batteries?

To achieve equalization of each single cell of the series battery pack, there are currently several methods:

1. A parallel equalization circuit is added to each of the battery cells of the battery pack to achieve the function of shunting. In this mode, when a battery first reaches full charge, the equalization device can prevent it from overcharging and convert excess energy into heat, continuing to charge the unfilled battery. This method is simple, but it will bring energy loss and is not suitable for fast charging systems.

2. Discharge each monomer one by one through the same load one by one before charging, and then perform constant current charging to ensure a more accurate equilibrium between the individual cells. However, for the battery pack, due to the physical differences between individuals, it is difficult to achieve a completely consistent ideal effect after each unit is deeply discharged. Even if the same effect is achieved after discharge, a new imbalance occurs during the charging process.

3, timing and sequencing, separate to the monomer accumulator battery to detection and homogeneous charge. On battery charging, can guarantee the battery pack for each of the battery will not charge or discharge before, thus to ensure that each battery in the battery is in normal working condition.

4, by using the principle of the time-sharing, by control and switch, the switch component to make additional battery current into voltage is relatively low in order to achieve the goal of equalizing charge. This method is efficiency is higher, but control is more complex.

5. The voltage parameters of each battery are used as equalization objects, so that the voltages of the batteries are restored. During equalization charging, the capacitor is alternately connected to the adjacent two batteries through the control switch, accepting the charging of the high voltage battery, and discharging to the low voltage battery until the voltages of the two batteries tend to be uniform. The equalization method better solves the problem of battery pack voltage imbalance, but the method is mainly used in the case of a small number of batteries.

6. The whole system is controlled by single-chip microcomputer, and the single battery has an independent set of modules. The module performs charge management on each of the individual cells according to the setting procedure, and automatically disconnects after the charging is completed. The method is relatively simple, but the cost is greatly increased when the number of single cells is large, and the system volume is also not reduced.

The page contains the contents of the machine translation.