Negative electrode for rechargeable lithium battery, and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-11088360-B2
Application number	US-201916240145-A
Country	US
Kind code	B2
Filing date	Jan 4, 2019
Priority date	Feb 9, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A negative electrode for a rechargeable lithium battery includes a current collector and a negative active material layer disposed on the current collector. The negative active material layer includes a conductive material including a linear-shaped carbon-based material having an average length of about 40 μm to about 250 μm and a dot-shaped carbon-based material, and a negative active material. A mixing ratio of the conductive material and the negative active material is a weight ratio of about 0.1:99.9 to about 2.0:98.0.

First claim

What is claimed is:

1. A negative electrode for a rechargeable lithium battery, comprising
a current collector; and
a negative active material layer disposed on the current collector, the negative active material layer including a conductive material including a linear-shaped carbon-based material having an average length of about 40 μm to about 250 μm and a dot-shaped carbon-based material, and a negative active material,
wherein a mixing ratio of the conductive material and the negative active material is a weight ratio of about 0.1:99.9 to about 2.0:98.0.

2. The negative electrode as claimed in claim 1 , wherein the mixing ratio of the conductive material and the negative active material is a weight ratio of about 0.3:99.7 to about 1.0:99.0.

3. The negative electrode as claimed in claim 1 , wherein the weight ratio of the linear-shaped carbon-based material to the dot-shaped carbon-based material is about 1:1 to about 1:10.

4. The negative electrode as claimed in claim 1 , wherein an amount of the conductive material is about 0.1 wt % to about 2.0 wt % based on 100 wt % of the negative active material layer.

5. The negative electrode as claimed in claim 1 , wherein an amount of the linear-shaped carbon-based material is about 0.01 wt % to about 0.4 wt % based on 100 wt % of the negative active material layer.

6. The negative electrode as claimed in claim 1 , wherein the average length of the linear-shaped carbon-based material is about 70 μm to about 250 μm.

7. The negative electrode as claimed in claim 1 , wherein an average diameter of the linear-shaped carbon-based material is about 1 nm to about 20 nm.

8. The negative electrode as claimed in claim 1 , wherein a volume density (bulk density) of the linear-shaped carbon-based material is less than or equal to about 0.1 g/cm 3 .

9. The negative electrode as claimed in claim 1 , wherein the linear-shaped carbon-based material includes a carbon nanotube, a carbon nano fiber, or a combination thereof.

10. The negative electrode as claimed in claim 1 , wherein a Raman R value of the linear-shaped carbon-based material is about 0.8 to about 1.3, wherein the Raman R value indicates an intensity ratio (R=Id/Ig, of a peak intensity (Id) of a D peak (about 1350 cm −1 to about 1360 cm −1 ) relative to a peak intensity (Ig) of a G peak (about 1580 cm −1 to about 1590 cm −1 )) in a Raman spectrum analysis.

11. The negative electrode as claimed in claim 10 , wherein the Raman R value is about 0.9 to about 1.1.

12. The negative electrode as claimed in claim 1 , wherein the dot-shaped carbon-based material is carbon black.

13. The negative electrode as claimed in claim 1 , wherein an average particle diameter (D50) of the dot-shaped carbon-based material is about 5 nm to about 100 nm.

14. The negative electrode as claimed in claim 1 , wherein a specific surface area (SSA) of the dot-shaped carbon-based material is about 60 m 2 /g to about 1000 m 2 /g.

15. The negative electrode as claimed in claim 1 , wherein the negative active material is a material that reversibly intercalates/deintercalates lithium ions, a lithium metal, a lithium metal alloy, a material being capable of doping/dedoping lithium, or a transition metal oxide.

16. The negative electrode as claimed in claim 1 , wherein the negative active material is a carbon material that reversibly intercalates/deintercalates lithium ions.

17. A rechargeable lithium battery, comprising
the negative electrode according to as claimed in claim 1 ;
a positive electrode; and
a non-aqueous electrolyte.

18. The negative electrode as claimed in claim 1 , wherein the weight ratio of the linear-shaped carbon-based material to the dot-shaped carbon-based material is 1:3 to 1:10.

19. The negative electrode as claimed in claim 1 , wherein:
the linear-shaped carbon-based material includes a carbon nanotube, a carbon nano fiber, or a combination thereof, and
the dot-shaped carbon-based material is carbon black.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Cha Inoh
• Lee Jinhee
• Cho Chaewoong

Classifications

• H01M10/0525

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

• H01M10/0567

  characterised by the additives · CPC title

• H01M4/133 Primary

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title