Negative active material and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-12444736-B2
Application number	US-202318383082-A
Country	US
Kind code	B2
Filing date	Oct 24, 2023
Priority date	Jul 5, 2023
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A negative active material includes a core having a silicon-carbon composite and a polymer coating layer formed on the core, wherein the negative active material has about 1.02 to about 1.6 of a ratio of height of N1s peak occurring at about 400±about 0.5 eV relative to a height of N1s peak occurring at about 405±about 0.5 eV of a bonding energy, and about 1.02 to about 3.0 of a ratio of a height of C1s peak occurring at about 286.5±about 0.5 eV relative to a height of C1s peak occurring at about 290±about 0.5 eV when an X-ray photoelectron spectroscopy (XPS) is measured.

First claim

What is claimed is:

1. A negative active material, comprising:
a core comprising a silicon-carbon composite; and
a polymer coating layer on the core,
wherein the negative active material has about 1.02 to about 1.6 of a ratio of height of N1s peak occurring at about 400±about 0.5 eV relative to a height of N1s peak occurring at about 405±about 0.5 eV of a bonding energy, and about 1.02 to about 3.0 of a ratio of a height of a C1s peak occurring at about 286.5±about 0.5 eV relative to a height of C1s peak occurring at about 290±about 0.5 eV when an X-ray photoelectron spectroscopy is measured.

2. The negative active material as claimed in claim 1 , wherein the ratio of the height of the C1s peak appearing at about 286.5±about 0.5 eV relative to the height of the C1s peak appearing at about 290±about 0.5 eV of the bonding energy is about 1.03 to about 2.7, when the X-ray photoelectron spectroscopy is measured.

3. The negative active material as claimed in claim 1 , wherein the silicon-carbon composite comprises silicon nano particles and an amorphous carbon coating layer positioned on a surface of the silicon nano particles.

4. The negative active material as claimed in claim 1 , wherein the silicon-carbon composite further comprises crystalline carbon.

5. The negative active material as claimed in claim 1 , wherein the polymer coating layer includes a cross-linked polymer of a phenol group-included first repeating unit and an amine group-included second repeating unit.

6. The negative active material as claimed in claim 5 , wherein the phenol group-included first repeating unit is derived from a phenol compound with two or three OH groups.

7. The negative active material as claimed in claim 6 , wherein the phenol compound comprises pyrogallol, catechol, resorcinol, hydroquinone, phloroglucinol, or a combination thereof.

8. The negative active material as claimed in claim 5 , wherein the amine group-included second repeating unit is derived from an amine compound having two or three amine groups.

9. The negative active material as claimed in claim 8 , wherein the amine compound comprises polyethyleneimine, diethylenetriamine, triethylenetetramine, or a combination thereof.

10. The negative active material as claimed in claim 1 , wherein an amount of the polymer coating layer is about 0.2 wt % to about 2 wt % based on a total weight of 100 wt % of the negative active material.

11. The negative active material as claimed in claim 1 , wherein the polymer coating layer has a thickness of about 1 nm to about 10 nm.

12. The negative active material as claimed in claim 1 , wherein the negative active material is a mixing product of the silicon-carbon composite, a phenol compound with two to three OH groups, and an amine compound having three or more amine groups, the mixing product comprising a cross-linked structure.

13. The negative active material as claimed in claim 12 , wherein the cross-linked structure is a heat treatment product.

14. The negative active material as claimed in claim 1 , wherein the negative active material has a C—H peak appearing at a wavelength of about 2940 cm −1 to about 3000 cm −1 , a C—O first peak appearing at a wavelength of about 980 cm −1 to about 990 cm −1 , and a C—O second peak appearing at about 1150 cm −1 to about 1200 cm −1 in a FT-IR analysis graph.

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

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Hyejin
• Yoo Pil Jin
• Kim Deok-Hyun
• Kim Youngugk
• Nah Jaehou
• Choi Ilyoung
• Kang Eunji
• Park Sunil
• Kim Jaewon
• OH Doori
• Kim Yookyung
• Kim Narae
• Lee Banseok

Classifications

• H01M10/44

  Methods for charging or discharging (circuits for charging H02J7/00) · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M10/0525 Primary

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

• H01M2004/021

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