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

Patent metadata

Field	Value
Publication number	US-2023122468-A1
Application number	US-202217963010-A
Country	US
Kind code	A1
Filing date	Oct 10, 2022
Priority date	Oct 14, 2021
Publication date	Apr 20, 2023
Grant date	—

Abstract

Disclosed are a negative electrode for a rechargeable lithium battery and a rechargeable lithium battery including the same, the negative electrode including a current collector, a negative active material layer on the current collector, including a silicon-based negative active material, and an adhesive layer on the negative active material layer, wherein the adhesive layer has a thickness of about 5 μm or less, the adhesive layer has an area of about 50 area % based on the total area of the negative active material layer, and the adhesive layer is positioned in a dot pattern.

First claim

What is claimed is:

1 . A negative electrode for a rechargeable lithium battery, comprising:
a current collector; a negative active material layer on the current collector and comprising a silicon-based negative active material; and an adhesive layer on the negative active material layer, wherein the adhesive layer has a thickness of about 5 μm or less, the adhesive layer has an area of about 50 area % or less based on the total area of the negative active material layer, and the adhesive layer is positioned in a dot pattern.

2 . The negative electrode for a rechargeable lithium battery of claim 1 , wherein the adhesive layer has a thickness of about 1 μm to about 5 μm.

3 . The negative electrode for a rechargeable lithium battery of claim 1 , wherein the adhesive layer has an area of about 5 area % to about 50 area % based on the total area of the negative active material layer.

4 . The negative electrode for a rechargeable lithium battery of claim 1 , wherein the adhesive layer comprises an acryl-based binder and a fluorine-based binder.

5 . The negative electrode for a rechargeable lithium battery of claim 4 , wherein a mixing ratio of the acryl-based binder and the fluorine-based binder is about 75:25 by weight ratio to about 50:50 by weight ratio.

6 . The negative electrode for a rechargeable lithium battery of claim 4 , wherein the acryl-based binder comprises poly(meth)acrylic acid, poly(meth)acrylate, polymethyl(meth)acrylate, polyacrylonitrile, an acrylonitrile-styrene-butadiene copolymer, a copolymer thereof, a mixture thereof, or a combination thereof.

7 . The negative electrode for a rechargeable lithium battery of claim 4 , wherein the fluorine-based binder comprises polyvinylidene fluoride, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polyvinylidene fluoride-co-tetrafluoroethylene, polyvinylidene fluoride-co-trifluoro ethylene, polyvinylidene fluoride-co-trifluoro chloroethylene and polyvinylidene fluoride-co-ethylene, or a combination thereof.

8 . The negative electrode for a rechargeable lithium battery of claim 1 , wherein the negative electrode has bending strength of about 0.5 N or less.

9 . The negative electrode for a rechargeable lithium battery of claim 1 , wherein the negative electrode further comprises a carbon-based negative active material.

10 . A rechargeable lithium battery, comprising
a negative electrode of claim 1 ; a positive electrode; and an electrolyte.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Minjae
• Koo Kyoseon
• Nam Junghyun
• Moon Jeunggi
• Song Hyo-Jung
• Yang Mihwa
• You Duckjae
• Lee Jinhee
• Han Sungsoo

Classifications

• H01M2004/021

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

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/622

  being polymers · CPC title