Method for preparing cathode material lithium nickel cobalt aluminate for lithium ion battery by spray drying

Abstract

The invention relates to a method for preparing a cathode material lithium nickel cobalt aluminate for lithium ion battery by spray drying. A chemical general formula of the material is LiNi1-x-yCoxAlyO2, wherein x is more than 0.1 and less than 0.3, y is more than 0.01 and less than 0.15 and 1-x-y is more than 0 and less than 1. The preparation method comprises the following steps: mixing and sanding an insoluble nickel compound, an insoluble cobalt compound, an insoluble aluminum compound and a lithium compound for 2 to 8h, performing spray drying to obtain a lithium nickel cobalt aluminate precursor, and performing roasting to prepare the cathode material lithium nickel cobalt aluminate under an oxygen airflow by adopting a two-stage method. According to the method, spray drying is performed to rapidly evaporate water to obtain the uniform and dense spherical lithium nickel cobalt aluminate precursor after nickel, cobalt and aluminum are mixed on a nanometer scale by adopting an efficient sander, and the cathode material lithium nickel cobalt aluminate with stable electrochemical performance is finally obtained by stagewise roasting. The method is easy to operate and short in preparation cycle, and the product is high in quality and consistency, and can be continuously and industrially produced.

Description

technical field [0001] The invention relates to the technical field of positive electrode materials for lithium ion batteries, in particular to a method for preparing nickel cobalt lithium aluminate positive electrode materials by spray drying. Background technique [0002] Lithium-ion batteries have been widely used in 3C, power and energy storage fields due to their high energy density, good cycle performance, and environmental protection. In recent years, with the vigorous development of electric vehicles at home and abroad, cathode materials with high specific capacity and high energy density are called to meet market demand. [0003] Traditional lithium nickel oxide (LiNiO 2 ) has a high specific capacity, but poor cycle performance, and has a severe phase transition process during charge and discharge, which reduces the stability of the layered structure, thereby affecting the LiNiO 2 wide application. LiNiO 2 Through a small amount of Co 3+ and Al 3+ Co-doped ni...

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Problems solved by technology

[0005] The solid-phase method has a simple process and low cost, but nickel-cobalt-aluminum cannot be uniformly mixed at the atomic level, resulting in poor electrochemical performance of the product; the sol-gel method is complex and costly, and is not suitable for large-scale industrial production; the co-precipitation method The required preparation cycle is long, the process is numerous, and the uniformity of the electrochemical performance of the product is poor, and because the precipitation rate of aluminum ions is 10 times that of nickel and cobalt ions 18 times, nickel-cobalt-aluminum is difficult to precipitate homogeneously at the same time. Even though sodium metaaluminate is generally used as the aluminum source at present to solve the problem of homogeneous precipitation, the aqueous solution of sodium metaaluminate is unstable and easy to crystallize, which will not only cause The aluminum salt feed pipe is blocked, which brings inconvenience to the process control, and will cause the loss of aluminum and increase the cost

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