Negative Electrode and Secondary Battery

Patent metadata

Field	Value
Publication number	US-2025105254-A1
Application number	US-202318832184-A
Country	US
Kind code	A1
Filing date	Oct 13, 2023
Priority date	Oct 14, 2022
Publication date	Mar 27, 2025
Grant date	—

Abstract

A negative electrode for a secondary battery, includes a current collector, a first negative electrode active material layer, and a second negative electrode active material layer. The first negative electrode active material layer is provided on the current collector and includes a silicon carbon composite. The second negative electrode active material layer is provided on the first negative electrode active material layer and includes a silicon oxide. A secondary battery including the same is also provided.

First claim

1 . A negative electrode for a secondary battery, comprising:
a current collector; a first negative electrode active material layer provided on the current collector and comprising a silicon carbon composite; and a second negative electrode active material layer provided on the first negative electrode active material layer and comprising a silicon oxide, wherein a ratio (D 50,2nd /D 50,1st ) of an average particle diameter (D 50,2nd ) of the silicon oxide to an average particle diameter (D 50,1st ) of the silicon carbon composite is in a range of 0.75 to 1.5.

2 . The negative electrode for the secondary battery of claim 1 , wherein a discharge efficiency of the silicon carbon is in a range of 85% to 95%.

3 . The negative electrode for the secondary battery of claim 1 , wherein a discharge efficiency of the silicon oxide is in a range of 75% to 85%.

4 . The negative electrode for the secondary battery of claim 1 , wherein the ratio is in a range of 0.9 to 1.

5 . The negative electrode for the secondary battery of claim 1 , wherein the first negative electrode active material layer and the second negative electrode active material layer each further comprise a carbon-based active material.

6 . The negative electrode for the secondary battery of claim 5 , wherein the carbon-based active material comprises at least one of an artificial graphite or a natural graphite.

7 . The negative electrode for a secondary battery of claim 1 , wherein the silicon carbon composite in the first negative electrode active material layer is included in an amount of 1 wt % to 20 wt % based on 100 wt % of the first negative electrode active material layer, and the silicon oxide in the second negative electrode active material layer is included in an amount of 1 wt % to 20 wt % based on 100 wt % of the second negative electrode active material layer.

8 . The negative electrode for the secondary battery of claim 1 , wherein a thickness of each of the first and second negative electrode active material layers is in a range of 10 μm to 150 μm.

9 . The secondary battery comprising the negative electrode of claim 1 , a positive electrode, and a separator.

10 . The secondary battery of claim 9 , wherein the positive electrode comprises a positive electrode active material including a lithium composite transition metal compound including nickel (Ni) or cobalt (Co).

11 . The secondary battery of claim 10 , wherein the lithium composite transition metal compound further comprises at least one of manganese (Mn) or aluminum.

Assignees

• Lg Energy Solution Ltd

Inventors

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

Classifications

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/36

  Selection of substances as active materials, active masses, active liquids · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/133 Primary

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

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title