Screening method for consistent matching of lithium-ion batteries using voltage recovery voltage difference

Abstract

The invention relates to the technical field of lithium ion battery sorting, and in particular relates to a screening method for lithium ion battery consistency grouping through voltage recovery difference. The method comprises the following steps: carrying out pre-detection, rejecting unqualified batteries, performing stage charge / discharge on batteries to be sorted, and sorting the batteries according to the voltage difference that the voltage of the discharged batteries is recovered. Compared with the prior art, the screening method has the advantages that simplicity is realized, the sorting procedures are greatly simplified, the operation is easy, the screening efficiency is high and the application prospect is good.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery sorting, in particular to a screening method for consistent matching of lithium-ion batteries by using voltage recovery pressure difference. Background technique [0002] At present, most of the power sources used to provide power in electric vehicles, mobile power supplies and other devices are assembled batteries, which are composed of dozens or hundreds of single batteries connected in series and parallel. In the assembled batteries, their life depends mainly on The single battery with the worst performance, and the poor performance of the single battery will affect other single batteries, and the raw materials, manufacturing process, production equipment and environmental reasons will lead to the deviation of the consistency of the battery, so it is necessary to check the consistency of each single battery. The battery packs are combined to make the capacity, internal resistance, s...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, when lithium-ion batteries are paired and combined in actual production, the method of matching capacity, internal resistance and voltage at the same time is mostly used for grouping. This method requires capacity sorting for each battery first, and then internal resistance, Voltage test, the test value is close to the group, this method is time-consuming and laborious, and the efficiency is extremely low

For example, Chinese patent CN1917368A discloses "a method for manufacturing an energy storage lithium battery pack and an energy storage lithium battery pack". The screening method used in the technical solution is based on parameters such as battery capacity, open circuit voltage, and static internal resistance. Carry out battery matching, and the reference internal resistance is static internal resistance, a series of electrochemical reactions will occur in the actual charging and discharging process of the battery, there is polarization internal resistance, the battery of the same capacity cannot be fully charged and discharged at the same time, so it will Affects the capacity and cycle life of the battery pack. The method of this combination is complicated and inefficient

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