Negative electrode active material for electric device and electric device using the same

Patent metadata

Field	Value
Publication number	US-10297360-B2
Application number	US-201415536878-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Dec 17, 2014
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A negative electrode active material includes a silicon-containing alloy having a composition represented by: Si x Sn y M z A a (A is unavoidable impurities, M is one or more transition metal elements, x, y, z, and a represent values of percent by mass, and 0<x<100, 0<y<100, 0<z<100, and 0≤a<0.5 and x+y+z+a=100). The silicon-containing alloy has a lattice image subjected to Fourier transform processing to obtain a diffraction pattern and a size determined as an average value of maximum five major axis diameters of regions having a periodic array from a Fourier image obtained by subjecting a diffraction ring portion present in a width of from 0.7 to 1.0 when a distance between Si regular tetrahedrons is 1.0 in this diffraction pattern to inverse Fourier transform is 10 nm or less.

First claim

The invention claimed is:

1. A negative electrode active material for an electric device comprising a silicon-containing alloy comprising a composition represented by the following Chemical Formula (I)
[Chemical Formula 1]
Si x Sn y M z A a   (I)

wherein in Chemical Formula (I) above, A is an impurity,
M is one or two or more transition metal elements,
x, y, z, and a represent values of percent by mass, and
0<x<100, 0<y<100, 0<z<100, and 0≤a<0.5 and x+y+z+a=100,
wherein a size of a periodic array region is 4.7 nm or less, the periodic array region being a crystallized region scattered in an amorphous silicon region, and
the silicon-containing alloy having a first phase containing amorphous silicon as a main component and a second phase containing a transition metal and silicon and is adjacent to the first phase.

2. The negative electrode active material according to claim 1 , wherein the size of the periodic array region is 2.5 nm or less.

3. The negative electrode active material according to claim 1 , wherein M in Chemical Formula (1) above is titanium (Ti).

4. The negative electrode active material according to claim 1 , wherein 7<z<100 in Chemical Formula (1) above.

5. The negative electrode active material according to claim 1 , wherein M is Al, and x, y, z, and a represent values of percent by mass, and 12≤x<100, 0<y≤45, and 0<z≤43.

6. The negative electrode active material according to claim 1 , wherein M is V, and x, y, z, and a represent values of percent by mass, and 27≤x<100, 0<y≤73, and 0<z≤73.

7. The negative electrode active material according to claim 1 , wherein a crystalline silicide phase is contained in the amorphous silicon region.

8. The negative electrode active material according to claim 1 , wherein the first phase is more amorphized than the second phase.

9. A negative electrode for an electric device comprising the negative electrode active material according to claim 1 .

10. An electric device comprising the negative electrode according to claim 9 .

Assignees

• Nissan Motor

Inventors

• Kaburagi Tomohiro
• Watanabe Manabu
• Chiba Nobutaka
• Miki Humihiro
• Tanimura Makoto

Classifications

• H01M4/386 Primary

  Silicon or alloys based on silicon · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/36

  Selection of substances as active materials, active masses, active liquids · CPC title