Preparation method of high power capacity lithium ion battery cathode material

Abstract

A preparation method of a high power capacity lithium ion battery cathode material uses natural spherical graphite to serve as raw materials, uses concentrated sulfuric acid to serve as an inserting layer agent, uses potassium permanganate to serve as an oxidizing agent, conducts expansion treatment at high temperature to obtain micro-expanded graphite, then enables the micro-expanded graphite in different proportions to be mixed with nanometer ganister sand, conducts ultrasonic dispersion, suction filtration and dying to obtain the micro-expanded graphite with the nanometer ganister sand inserted in layers, enables the micro-expanded graphite to be mixed and coated with carbon source carbon source according to certain proportion, and finally conducts carburizing sintering under inert gas shielding to prepare completely coated silicon carbon composite cathode material with sufficient obligated obligate inside. Electrochemistry shows that the silicon carbon composite material prepared by the preparation method has high specific capacity and cycling stability and is the ideal high power capacity lithium ion battery cathode material.

Description

technical field [0001] The invention relates to the field of batteries, in particular to a method for preparing a high-capacity lithium-ion battery negative electrode material. Background technique [0002] Since Japan's Sony Corporation took the lead in developing and commercializing lithium-ion batteries in 1990, lithium-ion batteries have developed rapidly. Nowadays, lithium-ion batteries have been widely used in many fields such as civilian and military. With the continuous advancement of science and technology, people have put forward more and higher requirements for the performance of batteries: the miniaturization and personalized development of electronic equipment requires batteries to have smaller volumes and higher specific energy output; aerospace energy requirements Batteries have cycle life, better low-temperature charge and discharge performance, and higher safety performance; electric vehicles require batteries with large capacity, low cost, high stability ...

AI Technical Summary

Problems solved by technology

For example, magnetron sputtering or chemical deposition is used to deposit silicon thin films on current collectors, chemical vapor deposition is used to deposit nano-silicon thin films on graphite surfaces, nano-Si-Ni alloys are used, and silicon-carbon composite materials are produced by high-energy mechanical ball milling. Silicon powder with an average particle size of 80 nanometers is used to make silicon-carbon composite materials. These methods can indeed improve the cycle performance of silicon to a certain extent, but the degree of improvement is limited, and the cycle performance of the material still cannot meet the needs.

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