Positive electrode and rechargeable lithium batteries

Patent metadata

Field	Value
Publication number	US-2025357488-A1
Application number	US-202519209308-A
Country	US
Kind code	A1
Filing date	May 15, 2025
Priority date	May 16, 2024
Publication date	Nov 20, 2025
Grant date	—

Abstract

Disclosed are a positive electrode, and a rechargeable lithium battery including the positive electrode, the positive electrode including a positive electrode current collector and a positive electrode active material layer on the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material, a binder, and a conductive material. The binder includes a siloxane-based repeating unit and an imide-based repeating unit, and the binder includes the siloxane-based repeating unit in an amount of about 1 wt % to about 49 wt %.

First claim

What is claimed is:

1 . A positive electrode, comprising:
a positive electrode current collector; and a positive electrode active material layer on the positive electrode current collector, wherein: the positive electrode active material layer includes a positive electrode active material, a binder, and a conductive material, the binder includes a siloxane-based repeating unit and an imide-based repeating unit, and the binder includes the siloxane-based repeating unit in an amount of about 1 wt % to about 49 wt %.

2 . The positive electrode as claimed in claim 1 , wherein the siloxane-based repeating unit comprises a siloxane group substituted or unsubstituted with at least one of an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, and an aryl group.

3 . The positive electrode as claimed in claim 1 , wherein the siloxane-based repeating unit includes a siloxane group substituted or unsubstituted with a methyl group.

4 . The positive electrode as claimed in claim 1 , wherein the siloxane-based repeating unit has a structure represented by Chemical Formula 1:

wherein, in Chemical Formula 1,
R 1 and R 2 each independently comprises a substituted or unsubstituted C1 to C5 alkyl group,
m is an integer in a range of 100 to 3,000, and
* indicates a position linked to another element.

5 . The positive electrode as claimed in claim 1 , wherein the imide-based repeating unit comprises at least one of an imide group and an ether group.

6 . The positive electrode as claimed in claim 1 , wherein the imide-based repeating unit comprises an aromatic ring.

7 . The positive electrode as claimed in claim 1 , wherein the imide-based repeating unit has a structure represented by Chemical Formula 3:

wherein, in Chemical Formula 3,
X 1 and X 2 each independently comprises at least one of O and S,
L 1 comprises at least one of a substituted or unsubstituted C1 to C5 alkylene group, and a substituted or unsubstituted C6 to C20 arylene group,
L 2 comprises a substituted or unsubstituted C6 to C20 arylene group,
R 11 and R 12 each independently comprises at least one of hydrogen, deuterium, a halogen, and a C1 to C5 alkyl group,
a 11 and a 12 are each independently an integer in a range of 1 to 3,
n is an integer in a range of 100 to 2,500, and
* indicates a position linked to another element.

8 . The positive electrode as claimed in claim 1 , wherein the imide-based repeating unit has a structure represented by Chemical Formula 4:

wherein, in Chemical Formula 4,
X 1 and X 2 each independently comprises at least one of O and S,
L 2 , L 11 and L 13 each independently comprises C6 to C20 arylene group,
L 12 comprises a substituted or unsubstituted C1 to C5 alkylene group,
R 11 and R 12 each independently comprises at least one of hydrogen, deuterium, a halogen, and a C1 to C5 alkyl group,
a 11 and a 12 are each independently an integer in a range of 1 to 3,
n is an integer in a range of 100 to 2,500, and
* indicates a position linked to another element.

9 . The positive electrode as claimed in claim 1 , wherein the binder comprises about 51 wt % to about 99 wt % of the imide-based repeating unit.

10 . The positive electrode as claimed in claim 1 , wherein the binder has a weight average molecular weight (Mw) in a range of about 100,000 g/mol to about 2,000,000 g/mol.

11 . The positive electrode as claimed in claim 1 , wherein the binder does not include fluorine.

12 . The positive electrode as claimed in claim 1 , wherein the positive electrode active material comprises at least one of lithium cobalt oxide, lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide, lithium nickel cobalt manganese oxide, lithium nickel manganese oxide, lithium manganese oxide, a lithium iron phosphate compound, and a lithium manganese iron phosphate compound.

13 . The positive electrode as claimed in claim 1 , wherein:
the positive electrode active material comprises lithium transition metal phosphate, and the lithium transition metal phosphate comprises one or more of the compounds represented by Chemical Formulas 11 to 15:

wherein, in Chemical Formula 11, 0.90≤a1≤1.5, 0≤x1≤0.4, and M 1 comprises at least one of Al, Ca, Ce, Cr, Cu, La, Mg, Mn, Mo, Nb, Ni, Sn, Sr, Ti, V, W, Y, Zn, and Zr,

wherein, in Chemical Formula 12, 0.90≤a2≤1.5, 0.1≤x2≤0.9, 0≤y2≤0.9, and M 2 comprises at least one of Al, Ca, Ce, Cr, Cu, La, Mg, Mo, Nb, Ni, Sn, Sr, Ti, V, W, Y, Zn, and Zr,

wherein, in Chemical Formula 13, 0.90≤a3≤1.5, 0≤x3≤0.4, and M 3 comprises at least one of Al, Ca, Ce, Cr, Cu, La, Mg, Mo, Nb, Ni, Sn, Sr, Ti, V, W, Y, Zn, and Zr,

wherein, in Chemical Formula 14, 0.90≤a4≤1.5, 0≤x4≤0.4, and M 4 comprises at least one of Al, Ca, Ce, Cr, Cu, La, Mg, Mo, Nb, Ni, Sn, Sr, V, W, Y, Zn, and Zr, and

wherein, in Chemical Formula 15, 0.90≤a5≤1.5, 0≤x5≤0.4, and M 5 comprises at least one of Al, Ca, Ce, Cr, Cu, La, Mg, Mo, Nb, Ni, Sn, Sr, V, W, Y, Zn, and Zr.

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

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Eunji
• Choi Jewon
• Lee Jungmin
• Nam Junghyun

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• C08G77/455

  containing polyamide, polyesteramide or polyimide sequences · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title