Method and device for testing reversible self-discharge capacity loss of battery cell

Abstract

The invention provides a method and a device for testing reversible self-discharge capacity loss of a battery cell. The method comprises the following steps: acquiring a first maximum capacity of a target battery cell in an initial state; performing a self-discharge aging test on the target battery cell based on the set battery cell capacity influence parameter, and calculating the total self-discharge capacity loss of the target battery cell; calculating a second maximum capacity of the target cell after the self-discharge aging test; and based on the first maximum capacity, the second maximum capacity and the total self-discharge capacity loss, determining the reversible self-discharge capacity loss of the target cell under the set cell capacity influence parameter. Therefore, accurate calculation of the reversible self-discharge capacity loss is realized, so that the reversible self-discharge capacity of the battery cell at any temperature, in any SOC state and when the battery cell is stored for any time can be accurately obtained; and an accurate data basis is provided for formulating a more reasonable battery use management strategy, predicting the service life of the battery more accurately, optimizing a battery cell manufacturing process more efficiently and improving the consistency of the battery cells.

Description

technical field [0001] The invention relates to the field of battery technology, in particular to a method and device for testing the reversible self-discharge capacity loss of a battery cell. Background technique [0002] Lithium-ion batteries are self-discharging whether they are in storage or in use. Self-discharge not only causes the battery capacity to decrease, but also causes the cell consistency to deteriorate. A battery pack contains dozens or even hundreds of cells. When the capacity of each cell and the consistency of the SoC state become poor, it will cause rapid degradation of the capacity of the entire battery pack, and eventually lead to the rapid end of the life of the battery pack. There are many reasons for the self-discharge of the battery cell, such as metal foreign matter introduced in the manufacturing process of the battery cell, lithium dendrites during the use of the battery cell, side reactions between the electrolyte and the positive and negative ...

AI Technical Summary

Problems solved by technology

[0005] In view of this, the embodiment of the present invention provides a battery cell reversible self-discharge capacity loss testing method and device to overcome the lack of quantitative calculation methods for reversible self-discharge caused by reversible self-discharge in the prior art

Images