Granted Patent B2

US 12,738,486 · App. 17/680,588 · Granted Sep 15, 2026

Inventors: Shushi Dou (Ningde, CN); Chunhua Hu (Ningde, CN); Yao Jiang (Ningde, CN); Qi Wu (Ningde, CN); Jinhua He (Ningde, CN); Bin Deng (Ningde, CN)

Assignee: CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED

H01M4/525H01M4/366H01M4/505H01M10/0525H01M2004/021H01M2004/028H01M2220/20

Abstract

Claims (103)

1 . A positive electrode active material, comprising bulk particles and an element M 1 -containing oxide coating layer applied on an exterior surface of each of the bulk particles,

wherein the bulk particles comprise a nickel-containing lithium composite oxide;

bulk phases of the bulk particles are uniformly doped with element M 2 ; and

a surface layer of the bulk particles is an exterior doped layer doped with element M 3 , wherein

element M 1 and element M 3 are selected from one or more of Mg, Al, Ca, Ce, Ti, Zr, Zn, Y, and; and

element M 2 comprises one or more of Si, Mo, V, Ge, Se, Nb, Rh, Pd, Te, and W;

wherein the nickel-containing lithium composite oxide is a compound represented by formula 1,

Li 1+a [Ni x Co y Mn z M 2 b M 3 d ]O 2-p X p   formula 1

in the formula 1, X is selected from one or more of F, N, P, and S, 0.5≤x<1, 0<y<0.3, 0<z<0.3, −0.2<a<0.2, 0<b<0.2, 0<d<0.2, 0≤p<0.2, x+y+z+b+d=1.

2 . The positive electrode active material according to claim 1 , wherein

when the positive electrode active material is in a 78% delithiated state, element M 2 has a valence higher than +3; or

when the positive electrode active material is in a 78% delithiated state, element M 2 has more than two different valence states, and element M 2 in the highest valence state has one or more valences of +4, +5, +6, +7, and +8.

3 . The positive electrode active material according to claim 1 ,

wherein a relative deviation σ of local mass concentration of element M 2 in the bulk particles is less than 35%;

wherein the relative deviation σ is measured as following:

the relative deviation σ of local mass concentration of element M 2 in the bulk particles is calculated according to the following equation (1):

σ

=

max

⁢

{

❘

"\[LeftBracketingBar]"

η

1

-

η

_

❘

"\[RightBracketingBar]"

,

❘

"\[LeftBracketingBar]"

η

2

-

η

_

❘

"\[RightBracketingBar]"

,

❘

"\[LeftBracketingBar]"

η

3

-

η

_

❘

"\[RightBracketingBar]"

,

…

,

❘

"\[LeftBracketingBar]"

η

n

-

η

_

❘

"\[RightBracketingBar]"

}

η

_

(

1

)

wherein an average mass concentration of element M 2 in the bulk particles is denoted as η in g/g; the mass concentration of element M 2 in μg/g at different sites in the bulk particles are respectively denoted as η 1 , η 2 , η 3 , . . . , η n , where n is a positive integer greater than or equal to 15.

4 . The positive electrode active material according to claim 1 , wherein a deviation ε of the concentration of element M 2 in the positive electrode active material with respect to an average mass concentration η in g/g of element M 2 in the bulk particles satisfies ε<50%;

wherein the deviation ε is calculated by equation (2):

ε

=

❘

"\[LeftBracketingBar]"

ω

-

η

_

❘

"\[RightBracketingBar]"

ω

(

2

)

where ω is global mass concentration of element M 2 in ppm in the positive electrode active material.

5 . The positive electrode active material according to claim 1 , wherein in the positive electrode active material,

a concentration of element M 1 ranges from 100 ppm to 2000 ppm;

a concentration of element M 2 ranges from 500 ppm to 5000 ppm; and

a concentration of element M 3 ranges from 400 ppm to 3000 ppm.

6 . The positive electrode active material according to claim 1 , wherein

element M 3 in the bulk particle has a mass concentration gradient decreasing from the exterior surface to the core of the bulk particle; and

a mass concentration of element M 3 in the exterior doped layer is less than a mass concentration of element M 1 in the coating layer.

7 . The positive electrode active material according to claim 1 , wherein element M 1 and element M 3 are both element L, wherein element L has a mass concentration gradient decreasing from the exterior surface to the core of the particle of the positive electrode active material, and element L is one or more of Mg, Al, Ca, Ce, Ti, Zr, Zn, Y, and B.

8 . The positive electrode active material according to claim 1 , wherein a ratio of a sum of the concentration of element M 1 and the concentration of element M 3 in the positive electrode active material to a volume average particle size D v 50 of the positive electrode active material ranges from 25 ppm/m to 1000 ppm/m.

9 . The positive electrode active material according to claim 1 , wherein

a thickness of the exterior doped layer is 10% to 30% of the bulk particle size; or

a thickness of the coating layer ranges from 1 nm to 200 nm.

10 . The positive electrode active material according to claim 1 , wherein the positive electrode active material further satisfies one or more of the following requirements (1) to (3):

(1) a volume average particle size D v 50 of the positive electrode active material ranges from 3 μm to 20 μm;

(2) a specific surface area of the positive electrode active material is 0.2 m 2 /g to 1.5 m 2 /g; or

(3) a tap density of the positive electrode active material ranges from 2.3 g/cm 3 to 2.8 g/cm 3 .

11 . A positive electrode plate, comprising a positive electrode current collector and a positive electrode active substance layer disposed on the positive electrode current collector, wherein the positive electrode active substance layer comprises the positive electrode active material according to claim 1 .

Assignments (2)

Priority Claims (1)

Continuity (2)

References Cited (49)