Charging system for multi-section series battery pack and charging method thereof

Abstract

The invention relates to the technical field of charging of a multi-section series battery pack, and aims to provide a charging system for a multi-section series battery pack and a charging method thereof. The charging system comprises a power supply circuit and a battery management circuit, wherein the power supply input end of the battery management circuit is electrically connected with the power supply output end of the power supply circuit; the battery management circuit comprises charging switch circuits, the charging switch circuits are divided into charging input switch circuits and charging output switch circuits, and multiple groups of charging input switch circuits and multiple groups of charging output switch circuits are correspondingly arranged. The invention further discloses a charging method based on the charging system for the multi-section series battery pack. Single batteries in the multi-section series battery pack can be independently charged in a balanced mode inturn in the later period of charging. The equalization charging function can be better provided for the battery pack, the equalization consistency is better, the efficiency is higher, and the charging and discharging cycle life of the battery is not reduced.

Description

technical field [0001] The invention relates to the technical field of charging a multi-series series battery pack, in particular to a charging system and a charging method for a multi-series series battery pack. Background technique [0002] Existing multi-cell rechargeable batteries in series, especially lithium batteries, must have real-time monitoring and protection during charging, discharging and overcharging because of safety, flammability and explosion problems. Multiple single-cell rechargeable batteries need to be connected in series or in parallel to achieve high voltage and large capacity. However, each single-cell battery inevitably has differences in capacity, performance, and internal resistance during production, so there will be voltage differences during charging and discharging. In the later stage of charging, the voltage imbalance is particularly obvious, and the problem of battery damage is prone to occur. In the later stage of charging, if the average...

AI Technical Summary

Problems solved by technology

However, the equalization process in the later stage of using this BMS is very long, which will prolong the charging time of the battery pack, because the battery needs to be discharged and then recharged. If there are overcharges in multiple cells during the charging process, it will inevitably Greatly increase the time of equalization charging

In addition, the equalization process of this BMS actually allows the battery to undergo one or more charge and discharge cycles, which directly causes the loss of the cycle life of the battery.

From the actual situation of the market, using a lithium battery pack with equalization function can better solve the late equalization problem during the charging process, but the cycle life of the whole battery pack is far lower than that of the battery pack using the first type of BMS. service life

[0006] Therefore, the existing technology cannot effectively solve the charge-discharge balance problem of a single cell in the battery pack, cannot effectively utilize the actual performance of the battery itself, and cannot even allow the battery to reach its due service life at the user end

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