Negative active material and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-12368153-B2
Application number	US-202318386068-A
Country	US
Kind code	B2
Filing date	Nov 1, 2023
Priority date	Apr 17, 2023
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

A negative active material, including a first active material including a silicon core and a carbon coating layer on the core, a carbon second active material having an aspect ratio of about 4 to about 100, and a crystalline carbon third active material.

First claim

What is claimed is:

1. A negative active material, comprising:
a first active material comprising a silicon core and a carbon coating layer on the core;
a carbon second active material consisting of crystalline carbon and having an aspect ratio of about 4 to about 100; and
a crystalline carbon third active material.

2. The negative active material as claimed in claim 1 , wherein the carbon second active material has an average length of a long axis of about 20 μm or more.

3. The negative active material as claimed in claim 1 , wherein the carbon second active material comprises artificial graphite.

4. The negative active material as claimed in claim 1 , wherein the carbon coating layer of the first active material comprises semi-crystalline carbon or amorphous carbon.

5. The negative active material as claimed in claim 1 , wherein the carbon coating layer of the first active material comprises semi-crystalline carbon, amorphous carbon, or a combination thereof.

6. The negative active material as claimed in claim 1 , wherein the silicon core of the first active material comprises silicon, SiO x , in which 0<x<2, or a combination thereof.

7. The negative active material as claimed in claim 1 , wherein the first active material has protrusions and depressions on a surface.

8. The negative active material as claimed in claim 1 , wherein the first active material has an urchin-type shape.

9. The negative active material as claimed in claim 8 , wherein the amorphous carbon comprises soft carbon, hard carbon, mesophase pitch carbide, sintered cokes, or a combination thereof.

10. The negative active material as claimed in claim 1 , wherein the negative active material comprises about 4 wt % to about 20 wt % of the first active material, about 20 wt % to about 48 wt % of the carbon second active material, and about 48 wt % to about 76 wt % of the crystalline carbon third active material based on a total weight of the negative active material.

11. The negative active material as claimed in claim 1 , wherein the crystalline carbon third active material comprises natural graphite, artificial graphite, or a combination thereof.

12. A rechargeable lithium battery, comprising:
a negative electrode comprising the negative electrode of claim 1 ;
a positive electrode; and
an electrolyte.

13. The negative active material as claimed in claim 1 , wherein the carbon second active material has an average length of a long axis of about 20 μm to about 100 μm.

14. The negative active material as claimed in claim 1 , wherein the carbon second active material has an aspect ratio of about 4 to about 50.

15. The negative active material as claimed in claim 1 , wherein the carbon coating layer of the first active material has a thickness of about 1 nm to about 2,000 nm.

16. The negative active material as claimed in claim 1 , wherein the first active material has a particle diameter of about 1 μm to about 9 μm.

17. The negative active material as claimed in claim 1 , wherein a mixing ratio of the carbon coating layer and the silicon material is a weight ratio of about 3:7 to about 5:5 in the first active material.

18. The negative active material as claimed in claim 1 , wherein the first active material has an urchin-type shape, a length from a surface to an end of a protrusion and depression that is protruded outwardly is than about 0 nm and about 100 nm or less.

19. The negative active material as claimed in claim 1 , wherein the carbon second active material is a rod-type crystalline carbon.

20. The negative active material as claimed in claim 1 , wherein the crystalline carbon third active material has a spherical shape.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Yookyung
• Kim Youngugk
• Lee Jungho
• Nah Jaehou

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title