A battery pack undervoltage protection circuit

Abstract

The invention discloses an under-voltage protection circuit of a battery pack. The under-voltage protection circuit comprises a main board control system, a battery management system and a battery pack. The battery pack is a battery array formed by series connection of a preset number of battery groups. The battery management system is used for detecting the voltages of each battery group according a preset period; and when the voltage of the battery group is lower than or equal to a preset over-discharging protection voltage, the output of the battery pack is turned off. The main board control system is used for obtaining a lowest voltage in the preset number of battery groups from the battery management system; and when the lowest voltage is lower than or equal to a preset under-voltage protection voltage, the main board control system is turned off in a soft stop manner. The preset under-voltage protection voltage is lower than the preset over-discharging protection voltage. According to the under-voltage protection circuit, the stored energy of the battery pack can be utilized fully and the under-voltage protection function of the main board control system is superior to the battery management system, so that any injury accident caused by sudden outage of the battery management system can be avoided.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a battery pack undervoltage protection circuit. Background technique [0002] When electric sports equipment, such as a balance car, is in use, its energy source is the battery pack. During the process of providing energy, the voltage of the battery pack will gradually decrease. When the voltage drops to the preset over-discharge protection voltage, the output needs to be turned off. Protect the battery itself, because excessive discharge will cause permanent damage to the battery, this part of the work is done by the battery management system (Battery Management System, BMS). However, if the battery pack suddenly loses power and the main board control system loses the energy source, the sports equipment will stop suddenly, and the user may lose balance, resulting in falling and injury. In order to avoid this situation, general electric sports equipment adopts a two-level prot...

AI Technical Summary

Problems solved by technology

However, if the voltage values ​​of each battery pack are inconsistent and the difference is too large, it is possible that the BMS will perform under-voltage protection before the main board control system. If you set the under-voltage protection voltage>>n*over-discharge protection voltage, the priority protection of the BMS can be greatly reduced. probability, but the storage energy utilization rate of the battery pack will be greatly reduced, increasing the cost of the product

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