Battery management system and battery management method

Abstract

The invention discloses a battery management system and a battery management method. The system comprises a battery pack, sub-string battery management systems and a general battery management system, wherein the battery pack is formed by parallel connection of a plurality of sub-string batteries; each sub-string battery is formed by connecting a plurality of single batteries in series; the quantity of the sub-string battery management systems is the same as that of sub-strings; two lead wires are led out from each connection point of the single batteries in each set of the sub-string battery, wherein one lead wire is directly connected with the sub-string battery management systems and the other lead wire is connected with the sub-string battery management systems through a thermistor; and the general battery management system is connected with the sub-string battery management system and a control system of an electric automobile. According to the battery management system and the battery management method, temperature and voltage faults can be found in the shortest time, damages and fire breakout on the battery pack can be avoided, and the safety performance of the battery pack is remarkably improved.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a battery management system and method. Background technique [0002] The battery management system (BMS, Battery Management System) is the link between the battery and the vehicle drive system, which can improve the utilization rate of the battery, prevent the battery from overcharging and discharging, prolong the service life of the battery, and monitor the state of the battery. [0003] At present, the composition of the power battery pack of an electric vehicle is relatively complicated. Usually, several small single cells are connected in parallel to form a module with a larger capacity, and then many modules are connected in series to form a battery pack with a higher voltage. There are even more complicated series-parallel schemes for motor power supply. Due to the large number of small cells in the above-mentioned modules, the battery management system can only monitor...

AI Technical Summary

Problems solved by technology

[0003] At present, the composition of the power battery pack of an electric vehicle is relatively complicated. Usually, several small single cells are connected in parallel to form a module with a larger capacity, and then many modules are connected in series to form a battery pack with a higher voltage. Motor power supply, and even more complex series and parallel schemes

Due to the large number of small cells in the above-mentioned modules, the battery management system can only monitor the module, and cannot specifically monitor the voltage and temperature of each cell. To reach the nearest temperature sensor, the BMS often fails to detect the fault in time, which may cause damage to the battery pack or even a car fire

If it is necessary to monitor each single battery, the battery management system is too large and complex, and the cost is expensive. This has always been an unsolved problem

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