Negative active material for rechargeable lithium battery and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-12191489-B2
Application number	US-202117190863-A
Country	US
Kind code	B2
Filing date	Mar 3, 2021
Priority date	Mar 3, 2020
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

A negative active material for a rechargeable lithium battery includes a secondary particle in which a plurality of natural graphite primary particles are agglomerated, the plurality of primary particles including natural graphite, and the secondary particle including pores, and an amorphous carbon positioned in the pores, wherein an area of the amorphous carbon is about 10% to about 30% based on a total area of 100% of the negative active material, in a cross-section of the negative active material.

First claim

What is claimed is:

1. A negative active material for a rechargeable lithium battery, the negative active material comprising:
a secondary particle in which a plurality of primary particles are agglomerated, the plurality of primary particles comprising natural graphite, and the secondary particle comprising pores; and
an amorphous carbon filled in the pores,
wherein an area of the amorphous carbon is 10% to 30% based on a total area of 100% of the negative active material, in a cross-section through a center diameter of the secondary particle of the negative active material, and
wherein the natural graphite is flake graphite.

2. The negative active material of claim 1 , wherein each primary particle of the plurality of primary particles has a particle diameter of about 5 μm to about 15 μm.

3. The negative active material of claim 1 , wherein the secondary particle has a particle diameter of about 8 μm to about 24 μm.

4. The negative active material of claim 1 , wherein the natural graphite is flake graphite having a long axis and a short axis, and a length of the long axis is about 5 μm to about 15 μm.

5. The negative active material of claim 1 , wherein the secondary particle further comprises the amorphous carbon on a surface of the secondary particle.

6. The negative active material of claim 1 , wherein the negative active material comprises the amorphous carbon at an amount of about 1 wt % to about 9 wt % based on a total weight of 100 wt % of the negative active material.

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

Assignees

• Samsung Sdi Co Ltd

Inventors

• Park Sunil
• Kim Narae
• Nah Jaehou
• Moon Joongho
• Soh Hyun
• Lee Eunjoo

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

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

• H01M10/44

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

• H01M10/0525

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

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title