cu for battery negative 9 the s 5 Preparation method of @c nanocomposite material

Abstract

The invention provides a Cu9S5@C nanocomposite material used for the negative electrode of a battery and a preparation method thereof. The preparation method comprises the following steps: with sulfur powder, copper acetate and ammonia water as reaction raw materials, carrying out a hydrothermal method so as to generate copper sulfide, carrying out annealing so as to obtain Cu9S5, coating glucose on the surface of Cu9S5 by utilizing the hydrothermal method, and carrying out annealing at a high temperature so as to obtain the Cu9S5@C nanocomposite material. According to the invention, carbon is coated on the surface of metal sulfide, so the disadvantages of poor cycle performance and stability of sulfide can be effectively compensated; cycle performance and stability of a material are improved; conductivity of the material can be increased; and the Cu9S5@C nanocomposite material used as an anode material of a lithium ion battery can effectively realize high capacity and good cycle stability and effectively improves performances of the battery. Testing results show that the lithium ion battery with the Cu9S5@C nanocomposite material prepared by using the preparation method provided by the invention as the negative electrode has good lithium-ion electric performance, stable specific capacity and good cycle performance, obtains the characteristic of fast-rising capacity after manifold cycles, and has the specific capacity increased to two times of the initial specific capacity after 90 cycles.

Description

technical field [0001] The invention relates to the field of electrochemistry, in particular to a Cu 9 S 5 @C Preparation methods of nanocomposites. Background technique [0002] With the development of science and technology, people have higher and higher requirements for batteries. Higher battery performance can provide convenience for human production and life. Lithium-ion batteries have high energy density, high charging efficiency, light weight, no memory effect, The advantages of high capacity retention, small self-discharge, long cycle life, and environmental friendliness are widely accepted and used in various fields, from small portable electronic devices to large automotive power sources. In the future, lithium-ion batteries will also have It has high potential to be applied in a wider range such as electronic equipment, communication industry, power battery and energy storage battery. Therefore, the development of high-performance lithium-ion batteries is of gr...

AI Technical Summary

Problems solved by technology

[0003] The negative electrode material of lithium-ion batteries has always been regarded as an important focus of improving the capacity of lithium-ion batteries. Today, lithium-ion batteries on the market mainly use graphite as the negative electrode, and the specific capacity of this material is only 372mAh / g, which cannot To meet the growing demand for high-capacity lithium-ion batteries, and the lithium intercalation potential of graphite is close to the lithium stripping voltage, which may cause the formation and growth of lithium dendrites and cause safety issues, so a new type of lithium-ion battery is needed Negative material

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