Briquetting and sintering method for synthesizing lithium titanate negative electrode material

Abstract

The invention discloses a preparation method of a lithium titanate negative electrode material. According to the invention, degradable lithium salt and anatase titanium dioxide are adopted as raw materials, and twice ball milling, briquetting, and sintering is adopted, such that the lithium titanate negative electrode material is synthesized. The preparation method comprises the steps that: the lithium salt and the anatase titanium dioxide are weighed according to a stoichiometric ratio in a general formula; the materials are well mixed by wet ball milling; drying and pre-sintering are carried out; the pre-sintered material is well mixed again by ball milling; and briquetting and sintering are carried out, such that the lithium titanate negative electrode material is obtained. Compared with a traditional solid-phase method, the method provided by the invention has the advantages of reduced sintering temperature, reduced sintering time, low cost, and simple operation. The synthesized product has the advantages of high electrochemical performance, high tap density, and good batch stability.

Description

Technical field: [0001] The invention relates to a synthesis method of a lithium titanate negative electrode material for a lithium ion secondary battery by briquetting and sintering, and belongs to the lithium titanate negative electrode material synthesis technology. Background technique: [0002] The rapid development of lithium-ion batteries depends on the development of new energy materials and the progress of comprehensive technologies. Among them, the exploration and research of new electrode materials, especially negative electrode materials, is particularly important. At present, most commercial negative electrode materials use graphite and other lithium-intercalated carbon materials as the negative electrode. Although compared with metal lithium, the cycle performance and safety performance have been greatly improved, but there is still passivation of the carbon surface during the first charge and discharge. The membrane causes the problem of large irreversible ...

AI Technical Summary

Problems solved by technology

[0003]At present, the main problems of lithium titanate are: the low electrical conductivity of the material leads to a low initial Coulombic efficiency, the high-rate discharge capacity decays quickly, and the high-rate characteristics It is one of the key factors that determine whether it can be commercialized; the low tap density of the material leads to low specific energy of the material, which limits its application in portable power supplies

The solid-phase method requires a higher calcination temperature and a longer calcination time, and it is easy to cause particle agglomeration and grain growth, which affects its electrochemical performance.

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