A method for uniform mixing of lithium salt and lithium ion cathode material precursor

Abstract

The invention relates to a uniform mixing method of lithium salt and a lithium ion cathode material precursor. The method is characterized by comprising the following steps: (1) a lithium formate saturated solution is prepared; and (2) precursor materials to be mixed are placed into a container, the temperature of the materials is kept at 80-120 DEG C under continuous stirring, the prepared lithium formate saturated solution obtained from the Step (1) is sprayed by a spraying method, and after spraying, stirring and thermal insulation continue until the materials are uniformly mixed and dried. Thus, the mixing is finished. According to the invention, lithium formate with high solubility is used as lithium salt, and the lithium formate solution uniformly coats the surface of the precursor by a spraying method. Thus, the uniform mixing effect is achieved. Under continuous stirring of the precursor, the lithium formate solution uniformly coats the surface of the precursor by the spraying method, and sintering is then carried out. By the method, uniformity of lithium can be guaranteed. The method is suitable for large-scale production, and consistency of products in the large-scale production can be guaranteed.

Description

technical field [0001] The invention relates to a method for uniformly mixing lithium salt and lithium ion cathode material precursor. Background technique [0002] The current lithium-ion cathode materials are mainly lithium cobaltate, lithium manganate, lithium nickelate, nickel-cobalt lithium manganate and lithium iron phosphate. Most of the lithium-ion cathode materials currently on the market are prepared by high-temperature solid-state sintering. Its characteristics are: the equipment and process preparation conditions are easy to control, and it is easy to realize industrialization. The preparation process usually mixes lithium salts with Ni, Co, Mn oxides, hydroxides or carbonates and then sinters them at high temperatures under different atmospheres to obtain lithium ion cathode materials. [0003] At present, the lithium salts used by sintering manufacturers are mainly lithium carbonate and lithium hydroxide. The lithium mixing process of the sintering factory i...

AI Technical Summary

Problems solved by technology

Since this solid-solid mixing cannot realize the uniform mixing of lithium in the precursor, the uneven distribution of lithium ions in the sintered product seriously affects the electrochemical performance of lithium-ion cathode materials.

At the same time, the commonly used lithium salts in the existing technology are lithium carbonate and lithium hydroxide. Due to their very low solubility, solid-liquid mixing cannot be achieved, so the uniform mixing of lithium salts with the precursor has not been solved.

[0005] Generally speaking, neither solid-solid mixing nor solid-liquid mixing in the prior art can achieve the uniform mixing of lithium source and lithium ion cathode material precursor

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