Activation method of lithium manganate battery

Abstract

The invention provides an activation method of a lithium manganate battery. A positive electrode active material of the lithium manganate battery is lithium manganate, the chemical formula of the lithium manganate is LiMn(1-x)NixO2, and x is equal to 0-0.1; the electrolyte of the lithium manganate battery contains vinylene carbonate and 1,4-butane sultone, and the volume ratio of vinylene carbonate to 1,4-butane sultone is 1: 2; the activation method comprises the following steps of measuring the open-circuit voltage of the lithium manganate battery when the storage voltage is stored for a preset time, comparing the open-circuit voltage is compared with the first preset voltage, carrying out different activation steps according to the comparison result, carrying out battery evaluation on the specific battery before activation according to the activation method, and then determining the proper activation step. The battery obtained through the activation step can recover the high capacity and has the high cycle performance.

Description

technical field [0001] The invention relates to an activation method for a lithium manganate battery. Background technique [0002] Lithium manganate has the characteristics of good safety, wide source of raw materials, and good rate performance. It is a commonly used active material for power lithium-ion batteries. However, the cycle performance of lithium manganate batteries is poor. At present, the more common method is to Add a combination of additives, the electrolyte contains vinylene carbonate and 1,4-butane sultone, wherein the volume ratio of vinylene carbonate and 1,4-butane sultone is 1:2, the invention People found that when the positive electrode material is nickel-doped lithium manganese oxide, the battery containing vinylene carbonate and 1,4-butane sultone in the electrolyte can obtain better high-temperature performance and cycle retention, but However, after long-term storage, vinylene carbonate and 1,4-butane sultone in the electrolyte will undergo side r...

AI Technical Summary

Problems solved by technology

[0002] Lithium manganate has the characteristics of good safety, wide source of raw materials, and good rate performance. It is a commonly used active material for power lithium-ion batteries. However, the cycle performance of lithium manganate batteries is poor. At present, the more common method is to Add a combination of additives, the electrolyte contains vinylene carbonate and 1,4-butane sultone, wherein the volume ratio of vinylene carbonate and 1,4-butane sultone is 1:2, the invention People found that when the positive electrode material is nickel-doped lithium manganese oxide, the battery containing vinylene carbonate and 1,4-butane sultone in the electrolyte can obtain better high-temperature performance and cycle retention, but However, after long-term storage, vinylene carbonate and 1,4-butane sultone in the electrolyte will undergo side reaction deposition on the surface of the positive electrode, resulting in an increase in the internal resistance of the battery and a decrease in capacity.