Negative Electrode and Secondary Battery

Patent metadata

Field	Value
Publication number	US-2024113283-A1
Application number	US-202318373614-A
Country	US
Kind code	A1
Filing date	Sep 27, 2023
Priority date	Sep 30, 2022
Publication date	Apr 4, 2024
Grant date	—

Abstract

A negative electrode for a secondary battery, including: a current collector; a first negative electrode active material layer provided on the current collector; and a second negative electrode active material layer provided on the first negative electrode active material layer, in which at least one of the first and second negative electrode active material layers includes a lithium-substituted carboxymethyl cellulose, and the second negative electrode active material layers includes a silicon-based active material, and a secondary battery including the same.

First claim

What is claimed is:

1 . A negative electrode for a secondary battery, comprising:
a current collector; a first negative electrode active material layer provided on the current collector, comprising a carbon-based active material; and a second negative electrode active material layer provided on the first negative electrode active material layer, comprising a silicon-based active material, wherein at least one of the first and second negative electrode active material layers comprises a lithium-substituted carboxymethyl cellulose, and wherein the silicon-based active material is not present in first negative electrode active material layer.

2 . The negative electrode of claim 1 , wherein the silicon-based active material comprises at least one of SiO x (0≤x<2), SiMy (M is a metal, 1≤y≤4), and Si/C.

3 . The negative electrode of claim 1 , wherein the second negative electrode active material layer comprising the silicon-based active material further comprises a carbon-based active material.

4 . The negative electrode of claim 3 , wherein the carbon-based active material comprises at least one of artificial graphite and natural graphite.

5 . The negative electrode of claim 3 , wherein the silicon-based active material is comprised in an amount of 1 part by weight to 40 parts by weight based on 100 parts by weight of a total active material comprised in the second negative electrode active material layer comprising the silicon-based active material.

6 . The negative electrode of claim 1 , wherein a sum of weights of the first and second negative electrode active material layers is 170 to 280 mg/25 cm 2 .

7 . A secondary battery comprising the negative electrode according to claim 1 , a positive electrode, and a separator.

8 . The secondary battery of claim 7 , wherein the positive electrode comprises a lithium composite transition metal compound comprising nickel (Ni) and cobalt (Co) as an active material.

9 . The secondary battery of claim 8 , wherein the lithium composite transition metal compound further comprises at least one of manganese and aluminum.

10 . The secondary battery of claim 7 , wherein a cell resistance performance (Ω) is 1.85 or less.

11 . The secondary battery of claim 7 , wherein a cell charge C-rate performance is 97% or more.

12 . The negative electrode of claim 1 ,
wherein a degree of substitution of the lithium-substituted carboxymethyl cellulose is 0.7 to 1.3.

13 . The negative electrode of claim 1 ,
wherein a molecular weight (Mn) of the lithium-substituted carboxymethyl cellulose is 300,000 to 1,000,000.

Assignees

• Lg Energy Solution Ltd

Inventors

• Kim Shulkee
• Lee Gyeongseop
• Kim Minsoo
• Park Kyutae
• Piao Lilin
• Baek Sora
• Yoo Kwang Ho
• Jung Wonhee

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• 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