Lithium ion battery negative material and preparation method thereof

Abstract

The invention discloses a lithium ion battery negative material and a preparation method thereof. The preparation method comprises the following steps: firstly adding metallic lithium to a non-aqueous solvent to dissolve to form a lithium solution; then adding a complexing agent of which the weight is 1-1.2 times more than the molar weight of the metallic lithium to the lithium solution to obtain a sol solution; then adding a negative material, stirring to obtain suspension liquid; then evaporating the suspension liquid to dryness at the temperature of 30-80 DEG C to obtain a precursor, uniformly grinding, then placing into a vacuum drying box, drying at 120 DEG C for 8-12 hours, and cooling with a furnace; and finally loading the powder obtained by grinding and drying into a corundum boat, placing the corundum boat into a cavity of an inert atmosphere furnace, and sintering at the temperature of 400-800 DEG C for 2-6 hours. According to the preparation method disclosed by the invention, previous lithiation treatment is carried out on the negative material by adopting the lithium sol solution, lithium ions are provided for the formation of an SEI film in a first-time charge-discharge process, the loss of positive lithium ions is reduced and the first-time charge-discharge coulomb efficiency, capacity and circulating property of the negative material are greatly improved.

Description

technical field [0001] The invention belongs to the field of lithium ion battery materials, and relates to a lithium ion battery negative electrode material and a preparation method thereof, in particular to a lithium ion battery pre-embedded lithium negative electrode material and a preparation method thereof. Background technique [0002] Lithium-ion batteries are a colossal success of the modern electrochemical discipline, with annual sales of $27 billion, the undisputed dominance of the rechargeable battery market. From the perspective of the development of lithium-ion batteries, the research on negative electrode materials plays a decisive role in the development of lithium-ion batteries. It is precisely because of the emergence of carbon materials that solves the safety problem of metal lithium electrodes that it really promotes the emergence and development of lithium-ion batteries. . The first charge and discharge coulombic efficiency is a very important performance...

AI Technical Summary

Problems solved by technology

There are also literature reports on the embedded lithium technology of negative electrode materials. Ma Shuhua et al. artificially deposited a layer of Li on the mesophase microsphere graphite (MCMB) 2 CO 3 or LiOH film to pre-lithiate the negative electrode. After Guo Huajun et al. pre-doped the graphite negative electrode with lithium, the capacity of the battery and the coulombic efficiency of the first charge and discharge were significantly improved. At the same time, other elements are also introduced, which still has unfavorable factors for the improvement of battery capacity.

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