Positive Electrode Active Material, Method for Preparing the Same, Positive Electrode Including the Same, and Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2026011724-A1
Application number	US-202319133102-A
Country	US
Kind code	A1
Filing date	Dec 1, 2023
Priority date	Dec 2, 2022
Publication date	Jan 8, 2026
Grant date	—

Abstract

The positive electrode active material includes a single particle composed of one single nodule, a quasi-single particle, which is a composite of at most 30 nodules, or a combination thereof. The positive electrode active material includes a lithium nickel-based oxide having a molar ratio of Ni of at least 60 mol % in the total transition metals, and a negative skewness factor (NSF) represented by Equation 1 below is 0.20 to 0.35:

NSF
=

(

D

5
⁢
0

-

D
10

)

/

I
max

.

[

Equation
⁢

1

]

D 50 is a particle diameter at a cumulative volume of 50% in a volume cumulative particle size distribution graph of the positive electrode active material. D 10 is a particle diameter at a cumulative volume of 10% in a volume cumulative particle size distribution graph of the positive electrode active material. I max is a maximum volume fraction in the volume cumulative particle size distribution graph of the positive electrode active material.

First claim

1 . A positive electrode active material comprising a single particle composed of one single nodule, a quasi-single particle, which is a composite of at most 30 nodules, or a combination thereof,
wherein: the positive electrode active material comprises a lithium nickel-based oxide having a molar ratio of Ni of at least 60 mol. % in the total moles of transition metals; and the positive electrode active material has a negative skewness factor (NSF) of from 0.20 to 0.35, wherein the NSF is calculated according to the following equation:

NSF
=

(

D

5
⁢
0

-

D
10

)

/

I
max

,

(
1
)

wherein D 50 (μm) is a particle diameter at a cumulative volume of 50% in a volume cumulative particle size distribution graph of the positive electrode active material, D 10 (μm) is a particle diameter at a cumulative volume of 10% in a volume cumulative particle size distribution graph of the positive electrode active material, and I max (%) is a maximum volume fraction in the volume cumulative particle size distribution graph of the positive electrode active material.

2 . The positive electrode active material of claim 1 , wherein the positive electrode active material has a D 50 of from 5.0 μm to 7.0 μm.

3 . The positive electrode active material of claim 1 , wherein the lithium nickel-based oxide is represented by the following formula:

wherein M 1 is Mn, Al, or a combination thereof, M 2 is at least one selected from the group consisting of Ba, Ca, Zr, Ti, Mg, Ta, Nb, or Mo, 1.0≤a≤1.5, 0.6≤b<1.0, 0<c<0.1, 0<d<0.2, 0≤e≤0.1, and 0<c+d+e<0.4.

4 . The positive electrode active material of claim 1 , wherein the positive electrode active material has an average particle diameter of nodules of from 1.0 μm to 7.0 μm.

5 . The positive electrode active material of claim 1 , wherein the positive electrode active material has a tap density (at a force of 108 N applied horizontally) of from 2.40 g/cc to 2.60 g/cc.

6 . The positive electrode active material of claim 1 , wherein the positive electrode active material has a pellet density (at a pressure of −9 ton) of from 3.60 g/cc to 3.80 g/cc.

7 . The positive electrode active material of claim 1 , wherein an initial resistance value of a monocell manufactured using the positive electrode active material is from 1.45 Ω to 1.50 Ω, wherein the initial resistance value is measured through a voltage change when 2.5 C of current is applied at an SOC of 50% for 10 seconds.

8 . A method for preparing the positive electrode active material according to claim 1 , the method comprising:
mixing a positive electrode active material precursor and a lithium raw material and performing primary firing to form a primary fired product; and pulverizing the primary fired product and performing secondary firing.

9 . The method of claim 8 , wherein the positive electrode active material precursor has a D 50 of from 4.0 μm to 10.0 μm.

10 . The method of claim 8 , wherein the pulverizing is performed by jet-mill pulverization.

11 . The method of claim 10 , wherein the jet-mill pulverization is performed under the conditions of from 2.0 bar to 4.0 bar of pressure and a speed range of from 1,000 rpm to 2,500 rpm.

12 . A positive electrode comprising the positive electrode active material of claim 1 .

13 . A lithium secondary battery comprising the positive electrode of claim 12 .

14 . The lithium secondary battery of claim 13 , having an initial resistance value of from 1.45 Ω to 1.50 Ω, wherein the initial resistance value is measured through a voltage change when 2.5 C of current is applied at an SOC of 50% for 10 seconds.

15 . The lithium secondary battery of claim 14 , wherein the initial resistance value is from 1.47 Ω to 1.50 Ω.

16 . The method of claim 11 , wherein the positive electrode active material precursor has a D 50 of from 4.0 μm to 10.0 μm.

17 . The positive electrode active material of claim 1 , wherein, the molar ratio of Ni is at least 70 mol. % in the total moles of transition metals.

18 . The positive electrode active material of claim 1 , wherein, the molar ratio of Ni is at least 80 mol. % in the total moles of transition metals.

19 . The method of claim 8 , wherein the positive electrode active material precursor has a nickel (Ni) content of at least 60 mol. % in a total metal content.

20 . The method of claim 8 , wherein the secondary firing is performed for 6 hours to 18 hours at a temperature of from 500° C. to 1,000° C.

Assignees

• Lg Energy Solution Ltd

Inventors

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

Classifications

• H01M10/052

  Li-accumulators · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2006/11

  Powder tap density · CPC title

• C01P2006/10

  Solid density · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title