Battery pack single battery consistency identification method and system

Abstract

The invention relates to a battery pack single battery consistency identification method and system. The method comprises the following steps that S1, capacity measurement is performed on each single battery in a battery pack so as to obtain the single batteries of consistent capacity; S2, internal resistance measurement is performed on each single battery of consistent capacity so as to obtain the single batteries of consistent internal resistance; and S3, polarization testing is performed on each single battery of consistent internal resistance so as to obtain the single batteries of consistent polarization, wherein the single batteries of consistent polarization are the single battery consistency identification result of the battery pack. The beneficial effects of the battery pack single battery consistency identification method and system are that the consistency of the battery pack is divided into the capacity consistency, the internal resistance consistency and the polarization consistency by the battery pack single battery consistency identification method, and the single batteries simultaneously meeting the three consistencies are the batteries of the qualified consistency so that the battery pack single battery consistency can be accurately and quantitatively identified.

Description

technical field [0001] The invention relates to the field of battery testing, in particular to a method and system for identifying the same monomers in a battery pack. Background technique [0002] As an energy storage and conversion device, batteries are widely used in various fields. In some fields such as electric vehicles, energy storage, electric tools, and consumer electronics, in order to increase the available energy and increase the output power, it is often necessary to form a battery pack by connecting batteries in series or in parallel. The initial performance inconsistency among the individual cells in the battery pack, and the amplification of the difference between the individual cells caused by continuous charge-discharge cycles, will accelerate the capacity decay of some individual cells, thereby causing the battery pack to fail prematurely. Therefore, the combination application of the battery not only requires the performance index of the single battery t...

AI Technical Summary

Problems solved by technology

The so-called characteristic curve method is to compare the actual charging or discharging curves of each single battery. However, it is difficult to find quantitative evaluation indicators for this method.

Although the capacity method and the internal resistance method can be quantitatively compared, even if the battery is determined to have the same capacity and internal resistance, there will still be inconsistencies in actual use, that is to say, the capacity and internal resistance cannot be simply used as an evaluation of the battery pack. index of sex

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