Coated anode material and method of preparing the same

Patent metadata

Field	Value
Publication number	US-2019260022-A1
Application number	US-201916403498-A
Country	US
Kind code	A1
Filing date	May 3, 2019
Priority date	Sep 25, 2015
Publication date	Aug 22, 2019
Grant date	—

Abstract

The present application provides a coated anode material and a method of preparing the same. The coated anode material has a core-shell structure, wherein the core-shell structure includes an inert core and a shell coated on the inert core, the shell comprises an anode active material, and the inert core comprises a non-active material. In the coated anode material, the anode active material of the shell is distributed over the non-active material of the inert core, and the coated anode material can overcome the volume change problem of silicon particles during lithium insertion/deinsertion to a certain extent and obtain a better cycle performance and rate performance.

First claim

What is claimed is:

1 . A method of preparing a coated anode material, comprising steps:
(a) dissolving naphthaline and sodium in an organic solvent, dispersing a non-active material in the organic solvent, and adding a silicon-containing compound into the organic solvent for reaction; and (b) washing and drying the product obtained from step (a), and then heat treating the product in an atmosphere of inert gas.

2 . The method of claim 1 , wherein in step (a), the naphthaline is firstly dissolved in the organic solvent, then the non-active material is added and dispersed in the organic solvent, then the sodium is added and dissolved in the organic solvent, and then the silicon-containing compound is added into the organic solvent for reaction.

3 . The method of claim 1 , wherein in step (a), a sodium naphthaline solution is firstly prepared by dissolving the naphthaline and the sodium in the organic solvent, then the non-active material is added and dispersed in the sodium naphthaline solution, and then the silicon-containing compound is added into the sodium naphthaline solution for reaction.

4 . The method of claim 1 , wherein in step (a), the silicon-containing compound and the non-active material are dispersed in the organic solvent, a sodium naphthaline solution is prepared by dissolving naphthaline and sodium in a solvent, and the sodium naphthaline solution is then dropped into the organic solvent which is dispersed with the silicon-containing compound and the non-active material.

5 . The method of claim 1 , wherein the organic solvent is at least one selected from the group consisting of ethylene glycol dimethyl ether, tetrahydrofuran, diethyl ether, 1,4-dioxane, benzene, toluene, xylene, ethyl acetate, n-hexane, cyclohexane, and carbonic ester.

6 . The method of claim 1 , wherein the non-active material is at least one selected from the group consisting of silicon carbide, tungsten carbide, titanium carbide, boron carbide, chromium carbide, silicon nitride, aluminium nitride, titanium nitride, zirconium nitride, chromium nitride, barium titanate, aluminium fluoride, titanium boride, copper powder, barium sulfate, and calcium carbonate.

7 . The method of claim 1 , wherein the silicon-containing compound is silicon tetrachloride.

8 . The method of claim 1 , wherein the organic solvent is ethylene glycol dimethyl ether or tetrahydrofuran, the non-active material is silicon carbide or silicon nitride, and the silicon-containing compound is silicon tetrachloride.

9 . The method of claim 1 , wherein the heat treatment is performed at a temperature between 200° C. and 1000° C. for a period between 1 h and 20 h.

Assignees

• Microvast Power Systems Co Ltd

Inventors

• Mattis Wenjuan Liu
• Luo Jianhai

Classifications

• H01M4/386 Primary

  Silicon or alloys based on silicon · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title