Negative electrode active material for electric device, negative electrode for electric device and electric device

Patent metadata

Field	Value
Publication number	US-9293764-B2
Application number	US-201214119034-A
Country	US
Kind code	B2
Filing date	May 22, 2012
Priority date	May 25, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A negative electrode active material for an electric device includes an alloy containing Si in a range from greater than or equal to 17% by mass to less than 90% by mass, Ti in a range from 10% by mass to 83% by mass exclusive, Ge in a range from 0% by mass to 73% by mass exclusive, and inevitable impurities as a residue. The negative electrode active material can be obtained with a multi DC magnetron sputtering apparatus by use of, for example, Si, Ti and Ge as targets. An electric device employing the negative electrode active material can achieve long cycle life, and ensure a high capacity and improved cycle durability.

First claim

The invention claimed is:

1. A negative electrode active material for an electric device, comprising an alloy containing Si in a range from 17% by mass to 46% by mass inclusive, Ti in a range from greater than or equal to 51% by mass to less than or equal to 68% by mass, Ge in a range from 3% by mass to 32% by mass inclusive, and inevitable impurities as a residue,
wherein the negative electrode active material is capable of suppressing an amorphous to crystalline phase transition when the Si is alloyed with Li.

2. The negative electrode active material for an electric device according to claim 1 , wherein the alloy contains Si in a range from greater than or equal to 27% by mass to less than or equal to 37% by mass, Ti in a range from greater than or equal to 51% by mass to less than or equal to 64% by mass, and Ge in a range from greater than or equal to 9% by mass to less than or equal to 12% by mass.

3. The negative electrode active material for an electric device according to claim 1 , wherein the alloy contains Si in a range from greater than or equal to 27% by mass to less than or equal to 33% by mass, Ti in a range from greater than or equal to 57% by mass to less than or equal to 64% by mass, and Ge in a range from greater than or equal to 9% by mass to less than or equal to 10% by mass.

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

5. An electric device comprising the negative electrode active material according to claim 1 .

6. The electric device according to claim 5 that is a lithium ion secondary battery.

7. The electric device according to claim 5 , wherein a discharge capacity maintenance ratio is 91% or higher at a 50th cycle or is 50% or higher at a 100th cycle.

8. The electric device according to claim 7 , wherein an initial capacity is 876 mAh/g or higher.

9. A negative electrode for an electric device, comprising:
a negative electrode active material for said electric device, comprising an alloy containing Si in a range from 17% by mass to 50% by mass inclusive, Ti in a range from 20% by mass to 68% by mass inclusive, Ge in a range from 3% by mass to 63% by mass inclusive, and inevitable impurities as a residue,
wherein the negative electrode active material is capable of suppressing an amorphous to crystalline phase transition when the Si is alloyed with Li.

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

11. The electric device according to claim 10 , wherein a discharge capacity maintenance ratio is 83% or higher at a 50th cycle or is 40% or higher at a 100th cycle.

12. The electric device according to claim 11 , wherein an initial capacity is 749 mAh/g or higher.

13. A negative electrode active material for an electric device, comprising an alloy containing Si in a range from 24% by mass to 37% by mass inclusive, Ti in a range from 51% by mass to 68% by mass inclusive, Ge in a range from 8% by mass to 12% by mass inclusive, and inevitable impurities as a residue,
wherein the negative electrode active material is capable of suppressing an amorphous to crystalline phase transition when the Si is alloyed with Li.

14. A negative electrode for an electric device comprising:
the negative electrode active material of claim 13 .

15. An electric device comprising the negative electrode active material according to claim 13 , wherein a discharge capacity maintenance ratio is 91% or higher at a 50th cycle or is 50% or higher at a 100th cycle.

16. The electric device according to claim 15 , wherein an initial capacity is 876 mAh/g or higher.

Assignees

• Watanabe Manabu
• Yoshida Masao
• Nissan Motor

Inventors

• Watanabe Manabu
• Yoshida Masao

Classifications

• H01M10/052

  Li-accumulators · CPC title

• C23C14/06

  characterised by the coating material ({C23C14/0021} , C23C14/04 take precedence) · CPC title

• C22C28/00

  Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00 · CPC title

• C22C14/00

  Alloys based on titanium · CPC title

• H01M4/38 Primary

  of elements or alloys · CPC title