Sorting method and system for reuse of retired battery modules

Abstract

The invention discloses a sorting method and system for reuse of retired battery modules. The method comprises the steps that S1, qualified echelon modules are pre-selected according to a pre-selection rule; S2, the initial voltage of each battery cell in the echelon modules is measured, each battery cell is subjected to constant-current discharging to a set value, and after discharging is finished, standing is conducted for a first set time, and then the voltage of each battery cell is measured; S3, the echelon modules are charged to the upper limit total voltage; S4, after charging is finished, waiting is conducted for a second set time, the open-circuit voltage OCV1 and the alternating-current internal resistance R of the echelon modules are measured, then the echelon modules are transferred into a storage area, and after waiting is conducted for a third set time, the open-circuit voltage OCV2 of each echelon module is measured; S5, the k value of each echelon module is calculated; and S6, data in the step S3 and the step S5 are sorted and then classified according to set standards, and then the echelon modules are transferred into a production and assembly link according to grading standards for echelon utilization so as to form the finished product pack. According to the sorting method and system for reuse of the retired battery modules, the sorting process is simple and reliable, the processing time is short, and the requirement for mass production is met.

Description

technical field [0001] The present invention relates to the technical field of lithium batteries, and more specifically relates to a sorting method and system for reusing decommissioned battery modules. Background technique [0002] With the development of new energy vehicles, the lithium batteries carried by the first batch of new energy vehicles put into use have already reached or are about to reach the retirement conditions. In the face of more and more retired batteries, the step-by-step utilization in the existing technology generally puts the retired batteries first. Disassemble the battery pack into modules and perform capacity calibration, then measure the group internal pressure difference and AC internal resistance in the fully charged state or empty state, and then classify the modules according to these parameters, and finally classify the retired battery modules in the same category Assembled into a Pack to achieve the purpose of reusing the decommissioned batt...

AI Technical Summary

Problems solved by technology

[0002] With the development of new energy vehicles, the lithium batteries carried by the first batch of new energy vehicles put into use have already reached or are about to reach the retirement conditions. In the face of more and more retired batteries, the step-by-step utilization in the existing technology generally puts the retired batteries first. Disassemble the battery pack into modules and perform capacity calibration, then measure the group internal pressure difference and AC internal resistance in the fully charged state or empty state, and then classify the modules according to these parameters, and finally classify the retired battery modules in the same category Assembled into a Pack to achieve the purpose of reusing the decommissioned battery modules; the existing technology only screens the data of the decommissioned modules without any processing on the decommissioned modules. Retired, so the pass rate of this kind of screening method is extremely low, and the reorganized Pack still has problems such as large pressure difference within the group, insufficient overall capacity, and rapid decay of individual cells / modules, resulting in short Pack life.

Images