Improved lithium battery pack equalizing method and equalizing circuit thereof

Abstract

The invention provides an improved lithium battery pack equalizing method and an equalizing circuit thereof. The method comprises the steps of performing clustering analysis on various data in one time period of each monomer battery of a battery pack by using a clustering analysis method, classifying the battery pack, judging the voltage of each battery in real time by combining and performing the equalizing method, performing further selection on each previously obtained classification by current information such as charging and discharging currents, finally obtaining the monomer battery needing to be equalized in the battery pack and performing equalizing and maintaining on the monomer battery by controlling an equalizing circuit. In the operation process of the battery pack, various feature data of the batteries can be analyzed, the monomer battery needing to be subjected to equalized charging and equalized discharging is picked out, and the monomer battery needing to be equalized is equalized by connecting the battery to the equalizing circuit; historical battery voltage data are introduced, the influence of the battery with abnormal voltage and the voltage collecting precision is effectively avoided, the condition of inconsistent voltage and capacitance is effectively avoided by combining surplus capacity relevant factors such as SOC and SOH, the consistency of the battery pack is effectively ensured and the service life of the battery pack is further ensured.

Description

technical field [0001] The invention relates to the field of equalization of battery packs, in particular to an improved equalization method of lithium battery packs and an equalization circuit thereof. Background technique [0002] Electric vehicles, energy storage power stations, electric bicycles, etc. all need to use battery packs composed of series-connected single cells to meet the needs of high voltage, so any effective use of battery packs has become a key issue at present. Although lithium-ion battery technology has made great progress in recent years, and the various performances of lithium batteries have been significantly improved; however, the inconsistency between single cells in lithium battery packs still exists widely. There are differences in various parameters of lithium batteries in the production process, and these differences are manifested as inconsistencies in the internal resistance, capacity, open circuit voltage, charge and discharge voltage platfo...

AI Technical Summary

Problems solved by technology

However, the capacity-based equalization method needs to accurately estimate the SOC of the single battery. If the accuracy of the SOC cannot be guaranteed, the reliability of the equalization will be greatly reduced.

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