Modified Positive Electrode Material and Preparation Method Therefor, and Lithium Ion Battery

Patent metadata

Field	Value
Publication number	US-2023163275-A1
Application number	US-202117535602-A
Country	US
Kind code	A1
Filing date	Nov 25, 2021
Priority date	Nov 25, 2021
Publication date	May 25, 2023
Grant date	—

Abstract

The disclosure provides a modified positive electrode material, a preparation method therefor, and a lithium ion battery. The modified positive electrode material includes a core and a coating layer. The core contains Mn and Ni, the coating layer includes a first oxide coating layer coating on a surface of the core. A first element forming the first oxide coating layer is selected from one or more of a group of Si, Ti, V, Zr, Mo, W, Bi, Nb, and Au. The first element with a high-valent state can partially enter the surface core structure of the positive electrode material to occupy the sites of manganese ions, and form a chemical bond stronger than a Mn—O. Thus, 0 and Mn in the core structure are difficult to precipitate, and the coating layer is difficult to fall off in cycle process. Moreover, structural stability of the modified positive electrode material is improved.

First claim

What is claimed is:

1 . A modified positive electrode material, comprising:
a core, the core being a positive electrode material containing a manganese element and a nickel element; and a coating layer, the coating layer comprising a first oxide coating layer, the first oxide coating layer coating on a surface of the core, and a first element forming the first oxide coating layer comprising, one or more of a group consisting of Si, Ti, V, Zr, Mo, W, Bi, Nb, and Ru.

2 . The modified positive electrode material according to claim 1 , wherein the first element forming the first oxide coating layer is selected from one or more of a group consisting of Mo, W, and Bi.

3 . The modified positive electrode material according to claim 1 , wherein the total mole number of the core is m, and the mole number of the first oxide coating layer is greater than 0% m and smaller than or equal to 5% m.

4 . The modified positive electrode material according to claim 1 , wherein the modified positive electrode material further comprising: a second oxide coating layer, the second oxide coating layer coating on the surface of the core, and being arranged between the positive electrode material and the first oxide coating layer, and a second element forming the second oxide coating layer being selected from elements of Group IVB and/or Group VB.

5 . The modified positive electrode material according to claim 4 , wherein the second element forming the second oxide coating layer is selected from one or more of a group consisting of Ti, V, and Zr.

6 . The modified positive electrode material according to claim 4 , wherein the total mole number of the core is m, and the mole number of the second oxide coating layer is 0.01% m to 3.00% m.

7 . The modified positive electrode material according to claim 1 , wherein the core is a concentration gradient spherical particle; and from inside to outside in a radial direction, a mole percentage of the nickel element in all metal elements is gradually decreased, and a mole percentage of the manganese element in all the metal elements is gradually increased.

8 . The modified positive electrode material according to claim 7 , wherein a radius of the core is R; in a surface layer of the core, a mole percentage of the nickel element is 0% to 60% of the total mole number of all metal elements in the surface layer, and a mole percentage of the manganese element is 10% to 100% of the total mole number of all the metal elements in the surface layer; in an interior of the core, a mole percentage of the nickel element is 60% to 100% of the total mole number of all metal elements in the interior, and a mole percentage of the manganese element is 0% to 10% of the total mole number of all the metal elements in the interior; and the interior refers to a portion from a spherical center to R/2 in the radial direction of the spherical particle, and the surface layer refers to a portion from R/2 to R in the radial direction of the spherical particle.

9 . The modified positive electrode material according to claim 1 , wherein the modified positive electrode material is denoted by the following general formula: Li 1+i Ni x Co y Mn (1−x−y) M m O 2 .[MO 2 ] n , −0.05≤i≤0.2, 0.5≤x≤0.8, 0.05≤y≤0.3, 0≤z≤0.3, 0≤m≤0.03, and 0≤n≤0.05.

10 . A preparation method for the modified positive electrode material according to claim 1 , comprising:
providing a positive electrode material particle containing a manganese element and a nickel element, and performing a mechanical fusion treatment on a first oxide and the positive electrode material particle containing the manganese element and the nickel element to obtain the modified positive electrode material, wherein a first element of the first oxide is selected from one or more of a group consisting of Si, Ti, V, Zr, Mo, W, Bi, Nb, and Ru.

11 . The preparation method for the modified positive electrode material according to claim 10 , wherein the preparation method for the modified positive electrode material further comprising: performing a first heat treatment after the mechanical fusion treatment, to obtain the modified positive electrode material, while a temperature is 100 to 300° C. and a time of the first heat treatment is 3 to 5 h.

12 . The preparation method for the modified positive electrode material according to claim 10 , comprising:
providing a precursor particle containing a nickel element and a manganese element, mixing the precursor particle containing the nickel element and the manganese element with a lithium source, and performing a sintering treatment; water-washing a product obtained after the sintering treatment, and adding a salt formed by a second element in the water-washing process; performing a second heat treatment after the water-washing process, to obtain a particle coated with a second oxide coating layer; and performing a mechanical fusion treatment on the particle coated with the second oxide coating layer and a first oxide, to obtain the modified positive electrode material, wherein a first element of the first oxide is selected from one or more of a group consisting of Si, Ti, V, Zr, Mo, W, Bi, Nb, and Ru, and the salt formed by the second element and a second element of the second oxide are each selected from elements of Group IVB and/or Group VB.

13 . The preparation method for the modified positive electrode material according to claim 12 , wherein a temperature of the second heat treatment is 200 to 900° C,or 300 to 700° C., and a sintering time of the second heat treatment is 1 to 20 h, or 3 to 12 h.

14 . The preparation method for the modified positive electrode material according to claim 12 , wherein a metal element of a second metal salt is selected from one or more of a group consisting of Ti, V, and Zr.

15 . The preparation method for the modified positive electrode material according to claim 12 , wherein the modified positive electrode material is obtained through a first heat treatment after the mechanical fusion treatment, while a temperature of the first heat treatment is 100 to 300° C. and a time of the first heat treatment is 3 to 5 h.

16 . A lithium ion battery, comprising a positive electrode, wherein the positive electrode comprises the modified positive electrode material according to claim 1 .

Assignees

• Microvast Power Systems Co Ltd
• Microvast Inc

Inventors

• Yonemoto Bryan
• Guo Huijie
• Mattis Wenjuan Liu

Classifications

• C01G53/82

  Compounds containing nickel, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/525

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

• C01P2006/40

  Electric properties · CPC title

• C01G53/50 Primary

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title