Positive active material, positive electrode plate, electrochemical energy storage apparatus, and apparatus

Patent metadata

Field	Value
Publication number	US-11949093-B2
Application number	US-202017132567-A
Country	US
Kind code	B2
Filing date	Dec 23, 2020
Priority date	Dec 29, 2018
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

This application provides a positive active material, a positive electrode plate, an electrochemical energy storage apparatus, and an apparatus. The positive active material is Li x Ni y Co z M k Me p O r A m or Li x Ni y Co z M k Me p O r A m whose surface is provided with a coating layer. The positive active material is secondary particles, and a particle size D n 10 of the positive active material satisfies: 0.5 μm≤D n 10≤3 μm. In this application, particle morphology of the positive active material and the amount of micro powder in the positive active material are properly controlled, to effectively reduce side reactions between the positive active material and an electrolyte, decrease gas production of the electrochemical energy storage apparatus, and improve storage performance of the electrochemical energy storage apparatus without deteriorating energy density, cycle performance and rate performance of the electrochemical energy storage apparatus.

First claim

What is claimed is:

1. A positive active material, wherein
the positive active material is Li x Ni y Co z M k Me p O r A m or Li x Ni y Co z M k Me p O r A m whose surface is provided with a coating layer, wherein 0.85≤x≤1.15, 0<y<1, 0<z<1, 0<k<1, 0≤p≤0.1, 1≤r≤2, 0≤m≤1, m+r≤2, M is one or two selected from Mn and Al, Me is one or more selected from Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, Sr, Sb, Y, W, and Nb, and A is one or more selected from N, F, S, and Cl; and
the positive active material is secondary particles, a particle size D n 10 of the positive active material satisfies: 0.5 μm≤D n 10≤3 μm, a particle size D v 10 of the positive active material is 2.5 μm to 8 μm, and D n 10 and D v 10 satisfy 1≤D n 10×D v 10≤20, wherein
D n 10 is a corresponding particle size when a cumulative number distribution percentage of the positive active material reaches 10%, and
D v 10 is a corresponding particle size when a cumulative volume distribution percentage of the positive active material reaches 10%.

2. The positive active material according to claim 1 , wherein the particle size D n 10 of the positive active material satisfies 1 μm≤D n 10<2 μm.

3. The positive active material according to claim 1 , wherein the coating layer comprises one or more coating elements selected from Al, Ba, Zn, Ti, Co, W, Y, Si, Sn, B, and P.

4. The positive active material according to claim 1 , wherein the particle size D v 10 of the positive active material is 3 μm to 6 μm.

5. The positive active material according to claim 1 , wherein
a theoretical specific surface area BET 1 of the positive active material and an actual specific surface area BET 2 of the positive active material satisfy: 0.8≤(BET 2 −BET 1 )/BET 1 ≤5.5, wherein
BET 1 =6/(ρ× D v 50);

ρ is an actual density of the positive active material, measured in g/cm 3 ;
D v 50 is a corresponding particle size when the cumulative volume distribution percentage of the positive active material reaches 50%, measured in μm.

6. The positive active material according to claim 5 , wherein the actual specific surface area BET 2 of the positive active material is 0.1 m 2 /g to 0.8 m 2 /g.

7. The positive active material according to claim 5 , wherein the particle size D v 50 of the positive active material is 5 μm to 18 μm.

8. The positive active material according to claim 5 , wherein the particle size D v 50 of the positive active material is 8 μm to 15 μm.

9. The positive active material according to claim 1 , wherein a differential particle size distribution curve of the positive active material has one and only one peak.

10. A positive electrode plate, comprising the positive active material according to claim 1 .

11. An electrochemical energy storage apparatus, comprising the positive active material according to claim 1 .

12. An apparatus, wherein the apparatus is a vehicle and comprises the electrochemical energy storage apparatus according to claim 11 .

13. The positive active material according to claim 1 , wherein
the particle size D n 10 of the positive active material measured in μm and a particle size D v 10 of the positive active material measured in μm satisfy: 2≤D n 10 D v 10≤18.

14. The positive active material according to claim 1 , wherein a particle size D v 90 of the positive active material is 10 μm to 30 μm, and D v 90 is a corresponding particle size when the cumulative volume distribution percentage of the positive active material reaches 90%, measured in μm.

15. The positive active material according to claim 14 , wherein the particle size D v 90 of the positive active material is 12 μm to 25 μm.

16. The positive active material according to claim 1 , wherein in the Li x Ni y Co z M k Me p O r A m , 0.50≤y≤0.90, 0.05≤z≤0.2, 0.05≤k≤0.4, and 0≤p≤0.05.

17. The positive active material according to claim 16 , wherein in the Li x Ni y Co z M k Me p O r A m , 0.70≤y≤0.90, 0.05≤z≤0.2, 0.05≤k≤0.2, and 0≤p≤0.05.

Assignees

• Contemporary Amperex Technology Co Ltd
• Contemporary Amperex Technology Co Ltd

Inventors

• Du Rui
• Liu Na
• Liu Yongchao
• Wang Sihui
• Zhao Deyu
• Leng Xue

Classifications

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/525 Primary

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title