Natural graphite, modified natural graphite material prepared from natural graphite, preparation method and application

Abstract

The invention provides natural graphite, a modified natural graphite material prepared from the natural graphite, a preparation method and application. The natural graphite has the following characteristics that: (1) the granularity D50 is less than 10 mum, and the D90/D10 is less than 2.5; (2) the 002 surface spacing is 0.336 to 0.360, and I002/I110 is less than or equal to 35; (3) the saturationtap density is less than or equal to 0.6 g/cc and less than 1.3 g/cc; and (4) the specific surface area is less than or equal to 1.0 m<2>/g and less than or equal to 10.0 m<2>/g. The natural graphitewith characteristics of specific granularity, specific orientation, specific tap density and specific surface area is provided, and is adopted as the preparation raw material, such that the finally prepared modified natural graphite material has high isotropy so as to provide excellent rate performance and excellent cycle performance.

Description

technical field [0001] The invention belongs to the technical field of negative electrode materials, and relates to a natural graphite, a modified natural graphite material prepared therefrom, a preparation method and an application. Background technique [0002] Controlling CO as global warming intensifies 2 The amount of release has become an urgent and major challenge for human society. In the field of transportation, the development of new energy vehicles is the general trend. Governments of various countries have successively introduced various preferential policies and subsidies to promote the development of new energy vehicles. Driven by the policies, electric vehicles powered by lithium-ion batteries have developed rapidly. However, due to problems such as high price and slow charging of power batteries, electric vehicles have not been fully commercialized so far. How to reduce the price of power batteries and improve performance has become the focus of current rese...

AI Technical Summary

Problems solved by technology

[0004] CN107195903A discloses a small particle size natural graphite negative electrode material for lithium-ion power batteries and its preparation method. The invention adds a "two Material mouth", the collection particle size range is 5-25μm and the tap density is greater than 0.65g / cm 3 After new shaping, chemical purification, and pitch-coated carbonization, a natural graphite anode material with small particle size and high capacity is obtained, but its first Coulombic efficiency and rate performance are still poor.

This invention uses a specific resin to coat and modify graphite particles to prepare lithium-ion battery negative electrode materials. The rate performance and first-time Coulombic efficiency of the composite materials prepared by this method are not good.

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