Preparation method for positive electrode material of lithium ion battery

Abstract

The invention provides a preparation method for a positive electrode material of a lithium ion battery. A complexing agent is added to a lithium source solution firstly; the pH of the lithium source solution is adjusted to 5-7 to obtain lithium salt sol; a positive electrode material precursor is added to the lithium salt sol to be mixed to obtain paste; the solution is evaporated while stirring and heating to obtain dried gel; and the dried gel is calcined to obtain the positive electrode material of the lithium ion battery. According to the preparation method, the contact area between the lithium salt sol and the positive electrode material precursor is large, so that the uniform mixing between the lithium salt sol and the positive electrode material precursor can be facilitated; the rapid implementation of the reaction can be promoted in the high-temperature roasting process, so that the cost is saved; the prepared positive electrode material elements are uniform in distribution; and a more excellent electrochemical performance of the positive electrode material is realized.

Description

technical field [0001] The invention belongs to the technical field of lithium ion battery materials, and in particular relates to a preparation method of a lithium ion battery cathode material. Background technique [0002] Lithium-ion batteries have the characteristics of high specific energy, stable cycle, high voltage platform, low self-discharge rate and environmental friendliness, so they are widely used in the fields of 3C consumer electronics and power batteries. At the beginning of this century, under the background of the rapid development of the new energy field, finding a lithium-ion battery system with higher energy storage density, longer cycle life, and better safety performance has also become a research focus of scientific research institutes and enterprises. High-capacity and high-voltage technology routes have become the mainstream direction of development in the field of lithium-ion batteries today. The cathode materials used in these two technical rou...

AI Technical Summary

Problems solved by technology

However, the method of mechanical mixing has a great destructive effect on the shape of the precursor. For example, the precursor of the ternary material is prepared by the co-precipitation method, and its shape is generally a secondary spherical particle formed by the agglomeration of submicron primary grains.

Before it is made into a finished product, its spherical structure is relatively loose. If mechanical mixing is used, the shape of the precursor will be broken, and the finished product of the ternary material has low tap density and poor processing performance.

On the other hand, the time required for mechanical mixing and grinding is long, and the mixing is prone to inhomogeneity, which will also cause Li segregation during the sintering process and the result of low electrode material performance.

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