Method of Producing Positive Electrode Active Material for Lithium Secondary Battery and Positive Electrode Active Material for Lithium Secondary Battery Produced Thereby

Patent metadata

Field	Value
Publication number	US-2022216463-A1
Application number	US-202017606268-A
Country	US
Kind code	A1
Filing date	Nov 27, 2020
Priority date	Nov 28, 2019
Publication date	Jul 7, 2022
Grant date	—

Abstract

A positive electrode active material contains a lithium transition metal oxide in the form of a secondary particle in which primary particles are aggregated, wherein a zirconium-containing coating film is formed on the surface of the lithium transition metal oxide secondary particle and at the interface between the primary particles present inside the secondary particle. A method of making the positive electrode active material is also provided.

First claim

1 . A method of producing a positive electrode active material, comprising:
mixing lithium transition metal oxides in the form of a secondary particle in which primary particles are aggregated, a zirconium-containing raw material, and at least one sintering aid selected from the group consisting of Bi 2 O 3 , Sb 2 O 3 , Li 2 O, LiOH.H 2 O, Co 2 O 3 , and NiO to form a mixture; and heat treating the mixture to form a zirconium-containing coating film on a surface of the secondary particle and at an interface between the primary particles present inside the secondary particle.

2 . The method of claim 1 , wherein the zirconium-containing raw material is at least one selected from the group consisting of ZrO 2 , Zr(OH) 4 , Zr 1−x A x O 2 , wherein A is at least one element selected from the group consisting of Y, Ce, and Sc, and 0≤x≤0.99, and ZrH 2 .

3 . The method of claim 1 , wherein the zirconium-containing raw material is mixed in an amount such that an amount of zirconium is 50 ppm to 50,000 ppm with respect to a total weight of the positive electrode active material.

4 . The method of claim 1 , wherein the sintering aid is mixed in an amount of 0.01 mol to 1 mol per 1 mol of the zirconium-containing raw material.

5 . The method of claim 1 , wherein the heat treatment is performed at 300° C. to 1,000° C.

6 . The method of claim 1 , further comprising, subsequent to the heat treatment, washing the lithium transition metal oxide in which the zirconium-containing coating film is formed on the surface of the secondary particle and at the interface between the primary particles present inside the secondary particle.

7 . The method of claim 1 , further comprising forming a coating layer containing at least one coating element selected from the group consisting of B, Li, Al, F, W, Mo, Ti, and Nb on the surface of the lithium transition metal oxide in which the zirconium-containing coating film is formed on the surface of the secondary particle and at the interface between the primary particles present inside the secondary particle.

8 . A positive electrode active material comprising:
a lithium transition metal oxide in the form of a secondary particle in which primary particles are aggregated, wherein a zirconium-containing coating film is formed on a surface of the secondary particle and at an interface between the primary particles present inside the secondary particle.

9 . The positive electrode active material of claim 8 , wherein the positive electrode active material contains zirconium in an amount of 50 ppm to 50,000 ppm based on a total weight of the positive electrode active material.

10 . The positive electrode active material of claim 8 , wherein 1 atm % to 50 atm % of zirconium of a total zirconium contained in the lithium transition metal oxide is distributed inside the secondary particle.

11 . The positive electrode active material of claim 8 , wherein at least one element selected from the group consisting of Bi, Sb, Li, Ni, and Co is included inside the secondary particle.

12 . The positive electrode active material of claim 8 , wherein the lithium transition metal oxide is represented by Formula 1 below:
Li a Ni x Co y M 1 z M 2 w O 2   [Formula 1]
wherein M 1 is Mn, Al, or a combination thereof, and M 2 is at least one selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and 0.8≤a≤1.2, 0<x<1, 0<y<1, 0<z<1, and 0≤w≤0.1.

13 . The positive electrode active material of claim 8 , further comprising a coating layer formed on a surface of the lithium transition metal oxide secondary particle and containing at least one coating element selected from the group consisting of B, Li, Al, F, W, Mo, Ti, and Nb.

14 . A positive electrode for a lithium secondary battery comprising the positive electrode active material of claim 8 .

15 . A lithium secondary battery comprising the positive electrode for a lithium secondary battery according to claim 14 .

Assignees

• Lg Chemical Ltd

Inventors

• Kwak No Woo
• Lee Hyuck
• Mok Duck Gyun
• Son Min Hee

Classifications

• H01M4/1391 Primary

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

• C01G53/50

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

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion 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

• H01M10/052

  Li-accumulators · CPC title