Silicon oxide material, making method, negative electrode, lithium ion secondary battery, and electrochemical capacitor

Patent metadata

Field	Value
Publication number	US-9484159-B2
Application number	US-201314100513-A
Country	US
Kind code	B2
Filing date	Dec 9, 2013
Priority date	Dec 10, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A silicon oxide material having a cobalt content of 2-200 ppm is provided. A negative electrode is formed using the silicon oxide material as active material. A nonaqueous electrolyte secondary battery constructed using the negative electrode exhibits improved cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide.

First claim

The invention claimed is:

1. A silicon oxide material for nonaqueous electrolyte secondary battery negative electrodes, having a cobalt content of 2 to 18 ppm (parts by weight per million parts by weight).

2. The silicon oxide material of claim 1 which is in the form of particles having an average particle size of 0.1 to 30 μm and a BET specific surface area of 0.5 to 30 m 2 /g.

3. A negative electrode for use in nonaqueous electrolyte secondary batteries, made of a negative electrode material comprising the silicon oxide material of claim 1 .

4. A lithium ion secondary battery comprising the negative electrode of claim 3 , a positive electrode, and a lithium ion-conductive nonaqueous electrolyte.

5. An electrochemical capacitor comprising the negative electrode of claim 3 , a positive electrode, and a conductive electrolyte.

6. A method for preparing a silicon oxide material for nonaqueous electrolyte secondary battery negative electrodes of claim 1 , comprising the steps of:
heating a SiO gas-providing raw material at a temperature in the range of 1,100 to 1,600° C. under reduced pressure or in an inert gas to generate a SiO gas, said SiO gas-providing raw material having a cobalt content of 500 to 10,000 ppm, and
cooling the SiO gas to a temperature in the range of 500 to 1,100° C. for precipitation.

7. The method of claim 6 , wherein the SiO gas-providing raw material is a silicon oxide powder or a mixture of a silicon dioxide powder and a metal silicon powder.

Assignees

• Shinetsu Chemical Co

Inventors

• Fukuoka Hirofumi
• Saito Mitsugu
• Ueno Susumu
• Inukai Tetsuya

Classifications

• H01G11/04

  Hybrid capacitors · CPC title

• H01M4/483 Primary

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• H01G11/50 Primary

  specially adapted for lithium-ion capacitors, e.g. for lithium-doping or for intercalation · CPC title

• C01B33/18

  Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof (preparation of aerogels by dehydrating gels C01B33/158; treatment to enhance the pigmenting or filling properties C09C) · CPC title