Positive Electrode Active Material for Lithium Rechargeable Battery, Method of Producing the Same, and Lithium Rechargeable Battery Including the Same

Patent metadata

Field	Value
Publication number	US-2022246928-A1
Application number	US-202217719523-A
Country	US
Kind code	A1
Filing date	Apr 13, 2022
Priority date	Aug 24, 2018
Publication date	Aug 4, 2022
Grant date	—

Abstract

A surface of a LiCoO2-based positive electrode active material to have a rock salt crystal structure is provided. Specifically, a positive electrode active material for a lithium rechargeable battery is provided, including: a core particle containing lithium cobalt oxide doped with aluminum (Al); and a coating layer positioned on a surface of the core particle and containing a cobalt (Co)-based compound having a rock salt crystal structure. A method of producing the positive electrode active material is also provided using a solid-phase method. The positive electrode active material can be applied to a positive electrode, lithium rechargeable battery, battery module, battery pack, and the like.

First claim

1 . A method of producing a positive electrode active material for a lithium rechargeable battery, comprising:
mixing a core particle comprising lithium cobalt oxide doped with Al and a cobalt raw material comprising tricobalt tetraoxide (Co 3 O 4 ), cobalt (II) hydroxide (Co(OH) 2 ), or a mixture thereof; and calcining the mixture of the cobalt raw material and the core particle.

2 . The method of claim 1 , wherein:
in the calcining of the mixture of the cobalt raw material and the core particle, a phase of the cobalt raw material is changed into a cobalt-based compound having a rock salt crystal structure and a surface of the core particle is coated with the cobalt-based compound having a rock salt crystal structure.

3 . The method of claim 1 , wherein:
in the mixing of the cobalt raw material with the core particle, a weight ratio (core particle:cobalt raw material) of the core particle to the cobalt raw material is 1,000:0.2 to 1,000:10.

4 . The method of claim 1 , wherein:
in the calcining of the mixture of the cobalt raw material and the core particle, a calcination temperature is 800 to 1,200° C.

5 . The method of claim 1 , wherein:
in the calcining of the mixture of the cobalt raw material and the core particle, a calcination time is 2 to 10 hours.

6 . The method of claim 1 , wherein:
the positive electrode active material comprises: the core particle comprising lithium cobalt oxide doped with aluminum (Al); and a coating layer on a surface of the core particle, wherein the coating layer comprises a cobalt-based compound having a rock salt crystal structure.

7 . The method of claim 6 , wherein:
the cobalt-based compound having the rock salt crystal structure is cobalt(II) oxide.

8 . The method of claim 6 , wherein:
the core particle comprises:
a first region in which a crystal structure of the lithium cobalt oxide doped with Al is a layered structure; and
a second region in which a crystal structure of the lithium cobalt oxide doped with Al is a spinel structure.

9 . The method of claim 8 , wherein: the first region is represented by the following Formula 1,
Li a Co (1-x-y-z) Al x M1 y M2 z O 2   [Formula 1]
wherein M1 and M2 are each independently one selected from the group consisting of Ti, Mg, Zr, Ba, Ca, Ta, Nb, and Mo, and a, x, y, and z are values satisfying 0.95≤a≤1.05, 0<x≤0.02, 0≤y≤0.02, and 0≤z≤0.02, respectively.

10 . The method of claim 8 , wherein: the second region is represented by the following Formula 2,
Li a-m Co (1-x-y-z) Al x M1 y M2 z O 2   [Formula 2]
wherein M1 and M2 are each independently one selected from the group consisting of Ti, Mg, Zr, Ba, Ca, Ta, Nb, and Mo, and a, x, y, z, and m are values satisfying 0.95≤a≤1.05, 0<x≤0.02, 0≤y≤0.02, 0≤z≤0.02, and 0<m<0.75, respectively.

Assignees

• Lg Chemical Ltd

Inventors

• Jo Chi Ho
• Hur Hyuck
• Kim Seul Ki
• Jung Wang Mo
• Han Gi Beom

Classifications

• H01M4/366 Primary

  as layered products · CPC title

• C01P2002/54

  one element only · CPC title

• 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

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• C01G51/40

  Complex oxides containing cobalt and at least one other metal element · CPC title