Process for preparing materials of silicon-porous carbon negative electrodes of lithium-ion batteries

Abstract

The invention relates to a process for preparing materials of silicon-porous carbon negative electrodes of lithium-ion batteries, which belongs to the technical field of preparing processes of chemical engineering electrode materials. The process comprises the steps of uniformly mixing magnesium powder or aluminum powder with silica, adding porous carbon, transferring obtained powder to a tube furnace, introducing inert gases, taking out products after a heating reaction is completed and the temperature of the tube furnace is cooled to the room temperature, adding the products into hydrochloric acid, and washing and filtering the products with deionized water till the pH of filtrate is neutral; and then adding the products into a hydrofluoric acid solution, washing and filtering with deionized water till the pH of filtrate is neutral, and drying filter cakes to obtain silicon-porous carbon composite materials of negative electrodes having nano-porous structures. The process is easy and practical, the controllability of preparation parameters is high, obtained products have nano-porous structures which provide a certain buffer space for volumetric expansion of silicon, simultaneously, the introduction of carbon enhances the electrical conductivity of materials, and the products have a high charging and discharging capacity and good cycling performances when serving as materials of negative electrodes of lithium-ion batteries.

Description

technical field [0001] The invention relates to a method for preparing a silicon-porous carbon negative electrode material for a lithium ion battery, and belongs to the technical field of chemical electrode material manufacturing technology. Background technique [0002] Since the successful development of lithium-ion batteries in the early 1990s, they have attracted much attention for their unique advantages such as high specific energy, high working voltage, wide application temperature range, low self-discharge rate, long cycle life, and no pollution. It is widely used in small portable electronic products such as mobile phones, digital cameras, and notebook computers. In recent years, in response to the negative impacts such as environmental pollution and sharp consumption of oil resources brought about by the rapid development of the automobile industry, the United States, Japan, China and other countries are actively developing electric vehicles EV and hybrid vehicles ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problems of serious pulverization, poor conductivity, fast capacity decay and poor cycle stability of the existing lithium-ion battery silicon negative electrode materials, to improve the electrochemical performance of the lithium-ion battery silicon negative electrode materials, and to provide a preparation Lithium-ion battery silicon-porous carbon anode material method

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