Method for controlling content of residual lithium on surface of layered high-nickel material

Abstract

The invention belongs to the technical field of lithium ion battery anode material modification methods, and discloses a method for controlling the content of residual lithium on the surface of a layered high-nickel material. The method comprises the following steps: (1) detecting the content x of the residual lithium on the surface of the layered high-nickel material; (2) calculating a theoretical mass of acid radical ions for removing y percent of the residual lithium according to the content x of the residual lithium, and preparing an organic acid aqueous solution; (3) washing the layered high-nickel material with the organic acid aqueous solution; and (4) performing separation and drying to obtain the layered high-nickel material capable of controlling the content of the residual lithium on the surface. According to the method disclosed by the invention, by washing the layered high-nickel material with the specific organic acid aqueous solution, the content of the residual lithiumon the surface of the material can be effectively controlled, so that reduction of the flowability of slurry during manufacturing of an electrode material due to a high content of the residual lithiumon the surface of the material is avoided. Through the adoption of the method, damage to a material structure can be avoided, and the condition that the electrochemical performance of the layered high-nickel material can be improved by controlling the content of the residual lithium is ensured.

Description

technical field [0001] The invention belongs to the technical field of modification methods for positive electrode materials of lithium ion batteries, and in particular relates to a method for controlling the residual lithium content on the surface of layered high-nickel materials. Background technique [0002] In recent years, the country has implemented a series of policies on new energy vehicles, which has greatly promoted the rapid development of power battery cathode materials. Due to the demand for high specific energy batteries in cars and the use of high-power and long-life batteries in passenger cars, the technical route makes ternary materials a better choice for cathode materials. It can be seen that ternary materials are facing huge opportunities in the power battery market. In 2017, the demand for cathode materials for power batteries will further increase, especially the market share of ternary materials with excellent performance will be further expanded. ...

AI Technical Summary

Problems solved by technology

Among them, layered high-nickel materials have become the first choice for major cathode material factories. Although layered high-nickel materials have the advantage of high energy density, their surfaces contain relatively high Li 2 CO 3 , LiOH and other alkaline substances, which make it easy to absorb water and inhibit the fluidity of the positive electrode material when it is mixed with organic solvents

At the same time, the residual lithium on the surface is easy to react with the electrolyte to produce gas, causing safety hazards

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