Battery positive electrode lithium supplement additive and preparation method thereof, positive electrode sheet and preparation method thereof, and lithium ion battery

Abstract

The invention provides a battery positive electrode lithium supplement additive and a preparation method thereof, a positive electrode sheet and a preparation method thereof, and a lithium ion battery. The preparation method of the battery positive electrode lithium supplement additive comprises the following steps: mixing a lithium source and a nickel source, calcining to obtain a lithium-rich material, mixing the lithium-rich material with water, washing with water, and then drying to obtain the battery positive electrode lithium supplement additive. According to the invention, by adding a water washing process, the residual alkali value of the positive electrodelithium supplement additive material is remarkably reduced, and by regulating and controlling the water washing process parameters, the residual alkali value of the positive electrode lithium supplement additive material can be further reduced; the low-residual-alkali positive electrode lithium supplement additive effectively relieves the damage of residual alkali to a binder in the preparation process of positive electrode slurry, and improves the flowability of the positive electrode slurry, so that the effects of uniform coating and improvement of the manufacturing quality of a positive electrode plate are achieved; and under the high-temperature condition, the low-residual-alkali positive electrode lithium supplement additive provided by the invention is not easy to decompose or react with an electrolyte solution, so that the reduction of the battery performance is effectively avoided.

Description

Technical field [0001] The present invention belongs to the technical field of lithium ion batteries, and more particularly to a battery positive electrode lithium additive, a positive electrode sheet, a method, and a lithium ion battery. Background technique [0002] Lithium-ion batteries are one of the most important components of new energy vehicles. In order to meet the rapid development needs of electric vehicles, the next generation of advanced electrode active materials with higher weight and volume capacity are required to achieve higher weight and volume energy density. . However, existing electrode materials have problems with high lithium loss in the first charge and discharge cycle, that is, the lithium in the positive electrode is irreversible to the negative electrode surface, forming a solid electrolyte interface layer, and cannot return to the positive electrode during subsequent discharge. The battery capacity is irreversible, and the loop life is shortened, and ...

AI Technical Summary

Problems solved by technology

Commonly used lithium-rich lithium nickel oxide materials contain more residual lithium sources, which will react with water and carbon dioxide in the air to form residual alkalis, and during the preparation of positive electrode slurry, these residual alkalis will interact with The binder reacts, and chemical gel is prone to occur during the stirring process of the positive electrode slurry, thereby affecting the quality of the positive electrode sheet. In addition, under high temperature conditions, the residual alkali will react with the electrolyte solution to generate gas or solid matter, increasing the Large battery gas or impedance, resulting in a decline in battery performance

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