Composite negative active material and method of preparing the same, negative electrode including composite negative active material, and lithium secondary battery including negative electrode

Patent metadata

Field	Value
Publication number	US-9923197-B2
Application number	US-201514872251-A
Country	US
Kind code	B2
Filing date	Oct 1, 2015
Priority date	Oct 2, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A composite negative active material including a piezoelectric material; and a negative active material. Also a negative electrode including the composite negative active material, and a lithium secondary battery including the negative electrode.

First claim

What is claimed is:

1. A composite negative active material comprising:
a piezoelectric material;
a non-carbonaceous negative active material; and
a carbonaceous negative active material,
wherein the non-carbonaceous negative active material has a maximum volume expansion of about 10% or more during an electrochemical reaction,
wherein the non-carbonaceous negative active material comprises at least one selected from silicon, germanium, aluminum, tin, and a titanium oxide, and
wherein the carbonaceous negative active material is contained in an amount of 4 weight percent to about 75 weight percent, based on a total weight of the composite negative active material.

2. The composite negative active material of claim 1 , wherein
the piezoelectric material comprises at least one selected from BaTiO 3 , PbTiO 3 , Pb[Zr x T 1-x ]O 3 wherein 0≤x≤1, KNbO 3 , LiNbO 3 , LiTaO 3 , Na 2 WO 3 , and ZnO.

3. The composite negative active material of claim 1 , wherein
an amount of the piezoelectric material is in a range of about 1 weight percent to about 90 weight percent, based on a total weight of the composite negative active material.

4. The composite negative active material of claim 1 , wherein
the non-carbonaceous negative active material has a maximum volume expansion of about 50% or more during an electrochemical reaction.

5. The composite negative active material of claim 4 wherein
the non-carbonaceous negative active material has a maximum volume expansion of about 300% or more during an electrochemical reaction.

6. The composite negative active material of claim 1 , wherein
an amount of the non-carbonaceous negative active material is in a range of about 1 weight percent to about 90 weight percent, based on a total weight of the composite negative active material.

7. The composite negative active material of claim 1 , wherein
the piezoelectric material is contained in an amount of about 4 weight percent to about 70 weight percent,
the non-carbonaceous negative active material is contained in an amount of about 4 weight percent to about 70 weight percent, and
the carbonaceous negative active material is contained in an amount of about 1 weight percent to about 75 weight percent, each based on a total weight of the composite negative active material.

8. The composite negative active material of claim 1 , wherein each of the piezoelectric material, the non-carbonaceous negative active material, and the carbonaceous negative active material are a distinct phase.

9. The composite negative active material of claim 1 , wherein the carbonaceous negative active material comprises at least one selected from a carbon nanotube, graphite, graphene, carbon black, and a carbonized polymer.

10. A composite negative active material comprising:
a first phase comprising a piezoelectric material;
a second phase comprising a non-carbonaceous negative active material; and
a third phase comprising a carbonaceous negative active material,
wherein the non-carbonaceous negative active material has a maximum volume expansion of about 10% or more during an electrochemical reaction,
wherein the non-carbonaceous negative active material comprises at least one selected from silicon, germanium, aluminum, tin, and a titanium oxide, and
wherein the carbonaceous negative active material is contained in an amount of 4 weight percent to about 75 weight percent, based on a total weight of the composite negative active material.

11. The composite negative active material of claim 10 , wherein the first phase is contained in an amount of about 4 weight percent to about 70 weight percent,
the second phase is contained in an amount of about 4 weight percent to about 70 weight percent, and
the third phase is contained in an amount of weight percent to about 75 weight percent, each based on a total weight of the composite negative active material.

12. A negative electrode comprising a composite negative active material according to claim 1 .

13. A lithium secondary battery comprising the negative electrode according to claim 12 .

14. A method of preparing a composite negative active material, the method comprising:
contacting a piezoelectric material, a carbonaceous negative active material, and a non-carbonaceous negative active material to form the composite negative active material,
wherein the non-carbonaceous negative active material has a maximum volume expansion of about 10% or more during an electrochemical reaction,
wherein the non-carbonaceous negative active material comprises at least one selected from silicon, germanium, aluminum, tin, and a titanium oxide, and
wherein the carbonaceous negative active material is contained in an amount of 4 weight percent to about 75 weight percent, based on a total weight of the composite negative active material.

15. The method of claim 14 , further comprising including a conductive agent in the contacting.

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Lee Byoungsun
• Jung Heechul
• Lee Kanghee
• Park Jinhwan
• Jung Changhoon
• Kim Kihong
• Kang Yoonsok
• Kim Dongyoung

Classifications

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/387

  Tin or alloys based on tin · CPC title