Negative active material and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-2025006926-A1
Application number	US-202418679644-A
Country	US
Kind code	A1
Filing date	May 31, 2024
Priority date	Jun 28, 2023
Publication date	Jan 2, 2025
Grant date	—

Abstract

A negative active material and a rechargeable lithium battery including the same, the negative active material including a core including a carbon material; and a carbon nitride on a surface of the core, and the rechargeable lithium battery including a negative electrode including the negative active material; a positive electrode; and an electrolyte.

First claim

What is claimed is:

1 . A negative active material, comprising:
a core comprising a carbon material; and a carbon nitride on a surface of the core.

2 . The negative active material as claimed in claim 1 , wherein the carbon nitride is represented by Chemical Formula 1,
C x N y   [Chemical Formula 1]
wherein 0<x<6 and 0<y<5.

3 . The negative active material as claimed in claim 1 , wherein the carbon nitride comprises C 3 N 4 , CN, C 2 N, C 3 N, C 2 N 2 , C 2 N 3 , C 5 N, C 5 N 2 or a combination thereof.

4 . The negative active material as claimed in claim 1 , wherein an amount of the carbon nitride is about 2 wt % to about 20 wt %, based on a total weight of the negative active material.

5 . The negative active material as claimed in claim 1 , wherein an amount of the carbon nitride is about 2 wt % to about 15 wt %, based on a total weight of the negative active material.

6 . The negative active material as claimed in claim 1 , wherein an amount of the core is about 80 wt % to about 98 wt %, based on a total weight of the negative active material.

7 . The negative active material as claimed in claim 1 , wherein the carbon material comprises crystalline carbon, amorphous carbon, or a combination thereof.

8 . The negative active material as claimed in claim 1 , wherein the carbon material comprises crystalline carbon.

9 . The negative active material as claimed in claim 8 , wherein the crystalline carbon comprises natural graphite, artificial graphite, or a combination thereof.

10 . A method of preparing a negative active material, the method comprising:
mixing a carbon material, a carbon nitride, and an acid to prepare an acid-included mixture; removing the acid from the acid-included mixture to prepare a mixture; and heat-treating the mixture.

11 . The method of preparing a negative active material as claimed in claim 10 , wherein the acid comprises sulfuric acid, hydrochloric acid, nitric acid, or a combination thereof.

12 . The method of preparing a negative active material as claimed in claim 10 , wherein the heat-treatment is performed under an inert atmosphere comprising nitrogen, argon, or a combination thereof.

13 . The method of preparing a negative active material as claimed in claim 10 , wherein the heat-treatment is performed at about 300° C. to about 900° C.

14 . The method of preparing a negative active material as claimed in claim 10 , wherein the carbon nitride is derived from a precursor comprising urea, melamine, dicyanamide, thiourea, cyanamide, or a combination thereof.

15 . The method of preparing a negative active material as claimed in claim 14 , wherein the carbon nitride is prepared by preliminarily heat-treating the precursor.

16 . The method of preparing a negative active material as claimed in claim 15 , wherein the preliminarily heat-treatment is performed at about 200° C. to about 700° C.

17 . A rechargeable lithium battery, comprising:
a negative electrode comprising the negative active material as claimed in claim 1 ; a positive electrode; and an electrolyte.

18 . The rechargeable lithium battery as claimed in claim 17 , wherein the negative electrode further comprises a silicon negative active material.

19 . The rechargeable lithium battery as claimed in claim 18 , wherein:
the negative electrode comprises the negative active material as a first negative active material and further comprises the silicon negative active material as a second negative active material, and a mixing ratio of the first negative active material and the second negative active material is about 99:1 to about 50:50 by weight ratio.

20 . The rechargeable lithium battery as claimed in claim 18 , wherein the silicon negative active material comprises Si, a Si—C composite, SiO x , in which 0<x<2, a Si-Q alloy, in which Q is an alkali metal, an alkaline earth metal, a Group 13 element, a Group 14 element, a Group 15 element, a Group 16 element, a transition metal, a rare earth element, or a combination thereof, but not Si, or a combination thereof.

Assignees

• Samsung Sdi Co Ltd
• Univ Industry Cooperation Group Ofkyung Hee Univ

Inventors

• Choi Ilyoung
• Park Min-Sik
• Park Sungmin
• Kim Taehee
• Kim Deok-Hyun
• Kim Youngugk
• Nah Jaehou
• Suh Joo Hyeong

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/483

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

• H01M4/386

  Silicon or alloys based on silicon · CPC title