Negative electrode and rechargeable lithium battery including the same

Patent metadata

Field	Value
Publication number	US-2026058154-A1
Application number	US-202519306570-A
Country	US
Kind code	A1
Filing date	Aug 21, 2025
Priority date	Aug 22, 2024
Publication date	Feb 26, 2026
Grant date	—

Abstract

In example embodiments, a negative electrode includes a current collector, and a negative electrode active material layer located on the current collector and including a negative electrode active material and a high ionic conductive binder. The high ionic conductive binder includes a first structural unit derived from a (meth)acrylic acid-based monomer, a second structural unit derived from a (C1-C10) alkylene glycol-based monomer, and a third structural unit derived from a zwitterionic vinyl-based monomer or a zwitterionic (meth)acryl-based monomer. A thickness of the negative electrode active material layer is greater than or equal to about 40 μm. The negative electrode according to some example embodiments can increase the energy density of a rechargeable lithium battery, while reducing the volume and weight of the rechargeable lithium battery and contributing to improving rapid charging performance.

First claim

What is claimed is:

1 . A negative electrode, comprising:
a current collector; and a negative electrode active material layer located on the current collector and including a negative electrode active material and a high ionic conductive binder; wherein the high ionic conductive binder comprises a first structural unit derived from a (meth)acrylic acid-based monomer; a second structural unit derived from a (C1-C10) alkylene glycol-based monomer; and a third structural unit derived from a zwitterionic vinyl-based monomer or a zwitterionic (meth)acryl-based monomer, and a thickness of the negative electrode active material layer is greater than or equal to about 40 μm.

2 . The negative electrode as claimed in claim 1 , wherein the thickness of the negative electrode active material layer is in a range of about 40 μm to about 1000 μm.

3 . The negative electrode as claimed in claim 1 , wherein the thickness of the negative electrode active material layer is in a range of about 100 μm to about 300 μm.

4 . The negative electrode as claimed in claim 1 , wherein the negative electrode active material comprises at least one of a carbon-based negative electrode active material, and a silicon-based negative electrode active material.

5 . The negative electrode as claimed in claim 1 , wherein the high ionic conductive binder is included in an amount in a range of about 0.2 wt % to about 5.0 wt % based on 100 wt % of the negative electrode active material layer.

6 . The negative electrode as claimed in claim 1 , wherein the high ionic conductive binder is included in an amount in a range of about 0.4 wt % to about 0.8 wt % based on 100 wt % of the negative electrode active material layer.

7 . The negative electrode as claimed in claim 1 , wherein the first structural unit is represented by Chemical Formula 1-1 or 1-2, and
the second structural unit is represented by Chemical Formula 2-1 or 2-2:

wherein, in Chemical Formulas 1-1 and 1-2:
R 1 is the same or different and each independently comprises one of a hydrogen atom and a C1 to C20 alkyl group; and
M1 comprises an alkali metal,

wherein, in Chemical Formulas 2-1 and 2-2:
M2 comprises an alkali metal, and
n is an integer between about 1 and about 100.

8 . The negative electrode as claimed in claim 1 , wherein the zwitterionic vinyl-based monomer or zwitterionic (meth)acryl-based monomer comprises at least one cationic functional group comprising at least one of a substituted or unsubstituted ammonium cation, an imidazolium cation, a pyrazolium cation, a pyridinium cation, a piperidinium cation, a piperazinium cation, a sulfide cation, a naphthalenium cation, and a guanidium cation.

9 . The negative electrode as claimed in claim 1 , wherein the zwitterionic vinyl-based monomer or zwitterionic (meth)acryl-based monomer comprises at least one anionic functional group comprising one of —SO 3 − , —CO 2 − , —O − , and —NR − ,
wherein R comprises a substituted or unsubstituted C1 to C10 alkyl group or a C1 to C10 haloalkyl group.

10 . The negative electrode as claimed in claim 1 , wherein the zwitterionic vinyl-based monomer or zwitterionic (meth)acryl-based monomer comprises at least one of a sulfobetaine-based monomer, a phosphobetaine-based monomer, a carboxybetaine-based monomer, and an imidazolium-based monomer.

11 . The negative electrode as claimed in claim 1 , wherein the third structural unit is represented by one of Chemical Formula 3-1 and 3-2:

wherein, in Chemical Formulas 3-1 and 3-2:
R 2 is the same or different, and each independently comprises one of a hydrogen atom and a C1 to C20 alkyl group;
R 3 is the same or different and each independently comprises one of a hydrogen atom and a C1 to C20 alkyl group;
L 1 comprises one of *—(C═O)—NR 3 —CH 2 —* and *—(C═O)—O—*; and
L 2 to L 4 each independently comprises one of a single bond and a C1 to C20 alkylene group.

12 . The negative electrode as claimed in claim 1 , wherein based on 100 wt % of the first structural unit, the second structural unit, and the third structural unit:
the first structural unit is included in an amount in a range of about 50 wt % to about 98 wt %, the second structural unit is included in an amount in a range of about 1 wt % to about 25 wt %, and the third structural unit is included in an amount in a range of about 1 wt % to about 25 wt %.

13 . The negative electrode as claimed in claim 1 , wherein the high ionic conductive binder further comprises a fourth structural unit derived from a (meth)acryl-based monomer.

14 . The negative electrode as claimed in claim 13 , wherein the (meth)acryl-based monomer comprises one of an amide group and a nitrile group.

15 . The negative electrode as claimed in claim 13 , wherein the fourth structural unit is represented by Chemical Formula 4:

wherein, in Chemical Formula 4, R 4 comprises one of a hydrogen atom and a C1 to C20 alkyl group.

16 . The negative electrode as claimed in claim 13 , wherein based on 100 wt % of the first structural unit, the second structural unit, the third structural unit, and the fourth structural unit:
the first structural unit is included in an amount in a range of about 30 wt % to about 70 wt %, the second structural unit is included in an amount in a range of about 1 wt % to about 15 wt %, the third structural unit is included in an amount in a range of about 1 wt % to about 15 wt %, and the fourth structural unit is included in an amount in a range of about 20 wt % to about 50 wt %.

17 . The negative electrode as claimed in claim 1 , wherein the high ionic conductive binder further comprises a lithium salt.

18 . The negative electrode as claimed in claim 1 , wherein the negative electrode active material layer further comprises an aqueous binder in addition to the high ionic conductive binder.

19 . The negative electrode as claimed in claim 18 , wherein the negative electrode active material layer further comprises a cellulose-based compound.

20 . A rechargeable lithium battery comprising:
the negative electrode as claimed in claim 1 ; a positive electrode; and an electrolyte.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Park Sujin
• Lee Kukjoo
• Jung Kyunghwa
• Cho Yunshik

Classifications

• C08F220/06

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• 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

• H01M10/052

  Li-accumulators · CPC title