Positive Electrode for Lithium Secondary Battery and Method for Manufacturing the Same

Patent metadata

Field	Value
Publication number	US-2025079433-A1
Application number	US-202318726544-A
Country	US
Kind code	A1
Filing date	Jan 11, 2023
Priority date	Jan 11, 2022
Publication date	Mar 6, 2025
Grant date	—

Abstract

disclosure A positive electrode for a lithium secondary battery includes a positive electrode collector; and a positive electrode active material layer which is formed on at least one surface of the positive electrode collector and includes a positive electrode active material, wherein the positive electrode active material layer has a pore volume of 7.0×10−3·cm3/g to 8.0×10−3·cm3/g. A method for preparing the positive electrode is also provided.

First claim

1 . A positive electrode for a lithium secondary battery comprising:
a positive electrode collector; and a positive electrode active material layer which is formed on at least one surface of the positive electrode collector, wherein the positive electrode active material layer comprises a positive electrode active material, and wherein the positive electrode active material layer has a pore volume of 7.0×10 −3 ·cm 3 /g to 8.0×10 −3 ·cm 3 /g.

2 . The positive electrode of claim 1 , wherein the positive electrode active material layer has a BET specific surface area of greater than 1.30 m 2 /g and less than 1.50 m 2 /g.

3 . The positive electrode of claim 1 , wherein the positive electrode active material comprises a small particle positive electrode active material and a large particle positive electrode active material having a greater D 50 than D 50 of the small particle positive electrode active material.

4 . The positive electrode of claim 3 , wherein the small particle positive electrode active material has D 50 of 2 μm to 5 μm.

5 . The positive electrode of claim 3 , wherein the large particle positive electrode active material has D 50 of 8 μm to 12 μm.

6 . The positive electrode of claim 3 , wherein a weight ratio of the small particle positive electrode active material to the large particle positive electrode active material is in a range of 1.0 to 2.0.

7 . The positive electrode of claim 1 , wherein the positive electrode active material comprises a lithium composite transition metal oxide represented by Formula 1 below:
Li 1+x (Ni a Co b Mn c M d )O 2   [Formula 1]
wherein, M is at least one selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, x, a, b, c, and d each satisfy −0.2≤x≤0.2, 0.50≤a<1, 0<b>0.25, 0<c≤0.25, 0≤d≤0.1, and a+b+c+d=1.

8 . The positive electrode of claim 1 , wherein the positive electrode active material comprises a lithium composite transition metal oxide containing at least 70 mol % of nickel with respect to a total number of moles of transition metals in the lithium composite transition metal oxide.

9 . The positive electrode of claim 1 , wherein the positive electrode active material layer has a porosity of 20% to 25%.

10 . A method for preparing a positive electrode for a lithium secondary battery, comprising:
coating at least one surface of a positive electrode collector with a positive electrode slurry containing a positive electrode active material to form a positive electrode active material layer; and rolling the positive electrode collector and the positive electrode active material layer, wherein the positive electrode active material layer after the rolling has a pore volume of 7.0×10 −3 ·cm 3 /g to 8.0×10 −3 ·cm 3 /g.

11 . The method of claim 10 , wherein the positive electrode active material layer after the rolling has a BET specific surface area of greater than 1.30 m 2 /g and less than 1.50 m 2 /g.

12 . The method of claim 10 , wherein the coating of the positive electrode slurry is performed by coating the positive electrode slurry on at least one surface of the positive electrode collector at a loading amount of 350 mg/25 cm 2 to 480 mg/25 cm 2 .

13 . The method of claim 10 , wherein a thickness of the positive electrode active material layer after the rolling is 66% to 72% with respect to a thickness of the positive electrode active material layer before the rolling.

14 . A lithium secondary battery comprising: the positive electrode for a lithium secondary battery according to claim 1 ; a negative electrode; a separator interposed between the positive electrode and the negative electrode; and an electrolyte.

15 . The positive electrode of claim 1 , wherein the positive electrode active material includes at least one of Li(Ni 0.83 Co 0.05 Mn 0.10 Al 0.02 )O 2 or Li(Ni 0.86 Co 0.05 Mn 0.07 Al 0.02 )O 2 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Kim Jong Woo
• Han Gi Beom
• Lho Eun Sol
• Jung Wang Mo
• Park Sang Min
• Lee Sang Wook
• Kim Seul Ki
• Kim Hyeong Il

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2004/021

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

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M4/0435 Primary

  Rolling or calendering · CPC title

• H01M2004/028

  Positive electrodes · CPC title