Positive Electrode Active Material and Positive Electrode Including the Same

Patent metadata

Field	Value
Publication number	US-2025070156-A1
Application number	US-202418945076-A
Country	US
Kind code	A1
Filing date	Nov 12, 2024
Priority date	Dec 15, 2022
Publication date	Feb 27, 2025
Grant date	—

Abstract

A positive electrode active material includes a nickel-based lithium composite metal oxide having a Ni content of 80 atm % or greater among transition metals except lithium, and in the form of a single particle or pseudo-single particle. The nickel-based lithium composite metal oxide has a coating layer positioned on the surface thereof, wherein the coating layer contains cobalt. The positive electrode active material also satisfies [Equation 1] 1≤XY/Z≤3, wherein X is the molar number (mol %) of Co in the coating layer based on 100 moles of the nickel-based lithium composite metal oxide, Y is the average particle diameter (μm) of nodules of the nickel-based lithium composite metal oxide, and Z is D 50 (μm) of the positive electrode active material, wherein Z is from 5 μm to 12 μm.

First claim

1 . A positive electrode active material comprising:
a nickel-based lithium composite metal oxide having a Ni content of 80 atm % or greater among transition metals except lithium, wherein the nickel-based lithium composite metal oxide is in a form of a single particle or pseudo-single particle; and a coating layer positioned on a surface of the nickel-based lithium composite metal oxide, wherein the coating layer includes cobalt, wherein the positive electrode active material satisfies Equation 1 below:

1
≤

XY
/
Z

≤
3

[

Equation
⁢

1

]

wherein, X (mol %) is a number of moles of Co in the coating layer based on 100 moles of the nickel-based lithium composite metal oxide, Y (μm) is an average particle diameter of nodules of the nickel-based lithium composite metal oxide, and Z (μm) is D 50 of the positive electrode active material, and
wherein the nickel-based lithium composite metal oxide is represented by Formula 2 below:
Li a Ni b Co c M 1 d M 2 e O 2   [Formula 2]

wherein, M 1 is Mn, Al, or a combination thereof, M 2 is one or more selected from the group consisting of W, Y, Ba, Ca, Ti, Mg, Ta, and Nb, and 0.8≤a≤1.2, 0.8≤b<1, 0<c<0.2, 0<d<0.2, and 0≤e≤0.1.

2 . The positive electrode active material of claim 1 , wherein X ranges from 1 mol % to 5 mol %.

3 . The positive electrode active material of claim 1 , wherein Y ranges from 1 μm to 10 μm.

4 . The positive electrode active material of claim 1 , wherein a ratio of Z to Y (Z/Y) ranges from 1 to 3.

5 . The positive electrode active material of claim 1 , wherein the positive electrode active material comprises a compound other than the nickel-based lithium composite metal oxide of Formula 2 in an amount ranging from 1 mol % to 5 mol % with respect to the nickel-based lithium composite metal oxide.

6 . The positive electrode active material of claim 1 , wherein the nickel-based lithium composite metal oxide has an average crystallite size ranging from 170 nm to 300 nm.

7 . The positive electrode active material of claim 1 , wherein the nickel-based lithium composite metal oxide has a strain value ranging from 200×10 −6 to 380×10 −6 .

8 . A positive electrode comprising a positive electrode active material layer including the positive electrode active material of claim 1 .

9 . The positive electrode of claim 8 , wherein the positive electrode active material is included in an amount ranging from 90 wt % to 100 wt % with respect to a total weight of the positive electrode active material layer included in the positive electrode.

10 . The positive electrode of claim 8 , wherein a ratio of the positive electrode active material having a size of from 5 μm to 7 μm with respect to an entire positive electrode active material is 80 vol % or greater.

11 . A lithium secondary battery comprising the positive electrode of claim 8 ; a negative electrode; and an electrolyte.

12 . The positive electrode active material of claim 1 , wherein Z ranges from 5 μm to 12 μm.

13 . The positive electrode active material of claim 1 , wherein Z ranges from 6 μm to 10 μm.

14 . The positive electrode active material of claim 1 , wherein Z ranges from 6.2 μm to 8 μm.

15 . The positive electrode active material of claim 1 , prepared by:
mixing the nickel-based lithium composite metal oxide and a solution containing a cobalt raw material to form a mixed solution; and heat treating a nickel-based lithium composite metal oxide powder obtained from the mixed solution to form the coating layer positioned on the surface of the nickel-based lithium composite metal oxide, wherein in the mixing, the cobalt raw material is mixed in an amount ranging from 0.8 parts by weight to 5 parts by weight based on 100 parts by weight of the nickel-based lithium composite metal oxide.

16 . The positive electrode active material of claim 15 , wherein in the mixing, the cobalt raw material is mixed in an amount ranging from 1.5 parts by weight to 3 parts by weight based on 100 parts by weight of the nickel-based lithium composite metal oxide.

17 . The positive electrode active material of claim 15 , wherein the heat treating is performed at a temperature ranging from 630° C. to 800° C.

18 . The positive electrode active material of claim 15 , wherein the heat treating is performed for 3 hours to 8 hours.

19 . An electric vehicle comprising the lithium secondary battery of claim 11 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Lho Eun Sol
• Hwang Jin Tae
• Oh Su Yeon
• Park Byun Chun
• Park Sang Min
• Lee Sang Wook
• Kim Seul Ki
• Kim Hyeong Il

Classifications

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M10/052 Primary

  Li-accumulators · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title