Preparation method of cobalt lithium silicate anode material for lithium ion battery

Abstract

The invention discloses a preparation method of a cobalt lithium silicate anode material for a lithium ion battery, comprising the following steps of: adding lithium hydroxide to imidazole type ion liquid, adding silicon dioxide to the mixture after stirring the mixture for 20-50min, adding cobaltous acetate to the mixture after stirring for 2-7h, and stirring again for 1-5h to uniformly mix the mixture; pouring the mixture into a high-pressure reaction kettle to make the mixture react for 5 hours to 7 days at 120-200 DEG C, and taking out products after the high-pressure reaction kettle is naturally cooled to room temperature; cleaning the products by distilled water or / and ethanol; putting the cleaned products into an oven for drying at 80-100 DEG C to obtain the cobalt lithium silicateanode material. The invention has the advantage that the method does not need the protection of inert gas and a sintering technique, thus the operation is more simply and convenient, and the preparedanode material has high purity and repeatability. In addition, the invention can realize the controllability of the phase and the appearance of the anode material and can ensure that the prepared anode material has better electrochemistry property.

Description

technical field [0001] The invention relates to a preparation process of a positive electrode material of a lithium ion battery, in particular to a preparation method of a lithium cobalt silicate positive electrode material used in a lithium ion battery. Background technique [0002] In recent years, lithium-ion batteries have been widely used in various fields of society as an efficient energy storage device, such as communication tools, electric equipment, and hybrid vehicles. However, lithium-ion batteries have been made of lithium cobalt oxide (LiCoO 2 ) positive electrode material, the actual usable capacity of this type of lithium cobalt oxide positive electrode material is only 135mAh / g, which leads to the capacity development of lithium ion batteries can not keep up with the progress of science and technology development, therefore, it is necessary to find new positive electrode materials to Improve the energy storage characteristics of the battery. [0003] At pre...

AI Technical Summary

Problems solved by technology

This high-temperature solid-phase reaction synthesis process is under the protection of an inert gas, and is sintered at a high temperature of 700 ° C to 900 ° C to realize the preparation of silicate cathode materials. Since this synthesis process requires the protection of an inert gas, it maintains a high temperature. The environment of pure inert gas is relatively difficult, which will lead to lower purity of the prepared silicate cathode material; on the other hand, if the inert gas is mixed with air, the performance of the prepared silicate cathode material is very poor, Even the required silicate cathode material may not be obtained, resulting in poor reproducibility of the silicate cathode material; in addition, since this synthesis process is sintered at a high temperature of 700 ° C to 900 ° C to synthesize silicate Therefore, the particles of the prepared silicate cathode material are large and uneven, and the particle size of the general particle is about 1 μm to 10 μm, which leads to poor electrochemical performance of the prepared silicate cathode material ; In summary, this synthesis process is not suitable for large-scale industrial production

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