Pre-charging method for improving lithium precipitation

Abstract

The invention discloses a pre-charging method for improving lithium precipitation. The method comprises four steps: 1, charging a battery through a small current, so as to form a solid electrolyte interface film on the surface of the battery cell of the battery; 2, continuously charging the battery until the voltage of the battery reaches a preset voltage range, wherein the current value of the current at step 1 is less than the current value of the current at step 2; 3, continuously charging the battery until the voltage of the battery reaches a preset voltage range, enabling the current value of the current at step 2 to be less than the current value of the current at step 3, and enabling the voltage of the battery to reach a charging cut-off current in a constant-voltage charging mode.According to the scheme, the battery is pre-charged through the smaller current, so that the solid electrolyte interface film is formed on the battery cell, and then charging is carried out through alarge-amplitude current step by step. The method can solve the lithium precipitation problem, improves the safety performance of the battery cell, and prolongs the service life of the battery cell.

Description

technical field [0001] The invention belongs to the field of lithium-ion battery charging, and in particular relates to a pre-charging method for improving lithium analysis. Background technique [0002] With the popularization of various mobile terminals, lithium-ion batteries have become mainstream power supply products due to their advantages such as high energy density and high average output voltage. In the increasingly popular power market, shortening the production cycle, increasing production capacity, and intentionally reducing the pre-charging time of lithium-ion batteries, but the current common practice is to increase the pre-charging current. Although this method can achieve immediate results, it also brings unavoidable Problems to avoid - Lithium precipitation, that is, metal lithium will be precipitated on the surface of the anode cell. This process is irreversible. Lithium deposition will reduce the safety performance and service life of the cell. Contents ...

AI Technical Summary

Problems solved by technology

[0002] With the popularity of various mobile terminals, lithium-ion batteries have become mainstream power supply products due to their advantages such as high energy density and high average output voltage. In the increasingly hot power market, shortening the production cycle, increasing production capacity, and intentionally reducing the pre-charging time of lithium-ion batteries, but the current common practice is to increase the pre-charging current. Problems to avoid - Lithium analysis, that is, metal lithium will be precipitated on the surface of the anode cell. This process is irreversible. Lithium analysis will reduce the safety performance and service life of the cell

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