Series lithium battery charging balancing circuit

Abstract

The invention discloses a series lithium battery charging balance circuit, which comprises a battery pack formed by connecting N battery cores in series, a voltage sampling circuit used for collectingthe voltages of each battery core in the battery pack, a DC-DC power supply module, a DC-DC output control circuit, a switch combination circuit, a switch drive circuit and an MCU control unit, wherein the DC-DC power supply module, the switch combination circuit and the battery pack are connected in sequence, the voltage sampling circuit is connected with the MCU control unit, the MCU control unit, the DC-DC output control circuit and the DC-DC power supply module are connected in sequence, and the MCU control unit, the switch driving circuit and the switch combination circuit are connectedin sequence. According to the invention, the voltages of each battery core in a battery pack can be effectively monitored, the whole battery pack or part of battery cores and even a single battery core are charged, the problem of balanced charging of each battery core in the battery pack is solved, the situation that each battery core needs to be screened due to individual difference is avoided, the tedious manufacturing procedures of various products are greatly reduced, the service life of the products is prolonged, and the safety risk of product use is reduced.

Description

technical field [0001] The invention relates to the technical field of battery charging, in particular to a charging balance circuit for lithium batteries connected in series. Background technique [0002] In recent years, more and more lithium-ion batteries have been used in medical, automotive, and consumer electronics. For different loads, it is often necessary to connect lithium batteries in series and parallel to meet the output requirements of different voltages and currents. However, the individual differences of the batteries in the series-parallel lithium battery pack and external influences such as the inconsistency of the operating temperature make the batteries in the battery pack have large differences and inconsistent capacities after working for a long time. The capacity of each battery cell is inconsistent, and it is easy to cause some cells to be fully charged during charging, but some cells cannot be fully charged (that is, undercharged), which seriously a...

AI Technical Summary

Problems solved by technology

However, the individual differences of the batteries in the series-parallel lithium battery pack and external influences such as the inconsistency of the operating temperature make the batteries in the battery pack have large differences and inconsistent capacities after working for a long time. The capacity of each battery cell is inconsistent, which can easily lead to the situation that some cells can be fully charged during charging, but some cells cannot be fully charged (that is, undercharged), which seriously affects the performance and life of the lithium battery pack.

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