Anode including graphite and silicon-based material having different diameters and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-12444732-B2
Application number	US-201917047593-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Oct 24, 2018
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

The present disclosure relates to an anode for a lithium secondary battery, wherein an anode material layer is formed on at least one surface of an anode current collector, and
the anode material layer includes large-particle graphite, a small-particle silicon-based material, fine-particle graphite, and carbon nanotube, and satisfies the following conditions 1 to 3: [Condition 1] Average diameter D50 of the large-particle graphite (D 1 ): 1 to 50 μm [Condition 2] Average diameter D50 of the small-particle silicon-based material (D 2 ): 0.155D 1 to 0.414D 1 [Condition 3] Average diameter D50 of the fine-particle graphite (D 3 ): 0.155D 1 to 0.414D 1 , or 0.155D 2 to 0.414D 2 .

First claim

The invention claimed is:

1. An anode for a lithium secondary battery, wherein an anode material layer is formed on at least one surface of an anode current collector, and the anode material layer comprises large-particle graphite, a small-particle silicon-based material, fine-particle graphite, and a carbon nanotube, and the large-particle graphite, the small-particle silicon-based material, and the fine-particle graphite satisfy the following ratios:
D 1 :D 2 =1:0.24-0.4 and D 1 :D 3 =1:0.16-0.3; or D 1 :D 2 =1:0.2-0.4 and D 2 :D 3 =1:0.33-0.4,
wherein D 1 is an average diameter D50 of the large-particle graphite selected in the range of 5 to 25 μm, D 2 is an average diameter D50 of the small-particle silicon-based material, and D 3 is an average diameter D50 of the fine-particle graphite,
wherein the small-particle silicon-based material comprises at least one selected from the group consisting of SiO x (0<x<2) and metal-doped SiO x (0<x<2), and
wherein the anode material layer comprises 60 to 95.5 wt % of the large-particle graphite, 0.5 to 30 wt % of the small-particle silicon-based material, 0.5 to 20 wt % of the fine-particle graphite, and 0.005 to 20 wt % of the carbon nanotube, based on a total weight of the large-particle graphite, the small-particle silicon-based material, the fine-particle graphite and the carbon nanotube.

2. The anode for a lithium secondary battery of claim 1 ,
wherein each of the large-particle graphite and the fine-particle graphite comprises at least one selected from the group consisting of natural graphite and artificial graphite.

3. The anode for a lithium secondary battery of claim 1 ,
wherein the metal-doped SiO x (0<x<2) is doped with at least one metal selected from the group consisting of Li, Mg, Al, Ca and Ti.

4. The anode for a lithium secondary battery of claim 1 ,
wherein the carbon nanotube has a structure of an aligned type or an entangle type.

5. The anode for a lithium secondary battery of claim 1 ,
wherein the carbon nanotube has an average diameter of 0.1 nm to 20 nm, and an average length of 100 nm to 5 μm.

6. The anode for a lithium secondary battery of claim 1 ,
wherein the anode material layer further comprises a conductive material and a binder.

7. The anode for a lithium secondary battery of claim 6 ,
wherein the conductive material and the binder are contained in an amount of 0.1 to 30 wt % based on a total weight of the anode material layer, respectively.

8. A lithium secondary battery comprising the anode for a lithium secondary battery of claim 1 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Choi Junghyun
• Song Hyeon Min
• Sung Joo Hwan
• Park Han Sol
• Cho Minsu
• Park Sunghae
• Kwak Jingoo
• Park Younguk
• Kim Sue Jin
• Jang Jinsu

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

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

• H01M10/0525

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

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/483

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