Positive Electrode Material, Producing Method Thereof, Positive Electrode and Lithium Secondary Battery Comprising the Same

Patent metadata

Field	Value
Publication number	US-2020185714-A1
Application number	US-201916701997-A
Country	US
Kind code	A1
Filing date	Dec 3, 2019
Priority date	Dec 10, 2018
Publication date	Jun 11, 2020
Grant date	—

Abstract

A positive electrode material and a method of producing thereof is provided. The positive electrode material having a bimodal particle diameter distribution and including large-diameter particles and small-diameter particles, wherein the small-diameter particle is a lithium composite transition metal oxide in the form of a single particle and containing a rock salt phase formed on a surface portion thereof.

First claim

1 . A positive electrode material comprising a bimodal particle size distribution, including a large-diameter particle and a small-diameter particle, wherein the large-diameter particle has a greater average particle diameter (D 50 ) than the small-diameter particle, wherein
the small-diameter particle is a lithium composite transition metal oxide having a nickel content of 80 atm % or greater in all transition metals of the lithium composite transition metal oxide, and the lithium composite transition metal oxide is a lithium composite transition metal oxide in a form of a single particle and containing rock salt phases having an average thickness of 10-30 nm on a surface portion thereof.

2 . The positive electrode material of claim 1 , wherein the small-diameter particle is a lithium composite transition metal oxide represented by [Formula 1] below:
Li x [Ni y Co z M 1 w M 2 v ]O 2   [Formula 1]
in Formula 1, M 1 is one or more selected from Mn and Al, M 2 is one or more selected from the group consisting of W, Cu, Fe, Ba, V, Cr, Ti, Zr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and 0.9≤x≤1.5, 0.8≤y<1, 0<z≤0.15, 0<w<0.2, and 0≤v≤0.2.

3 . The positive electrode material of claim 2 , wherein the small-diameter particle is a lithium composite transition metal oxide represented by [Formula 2] below:
Li x [Ni y Co z Mn w1 Al w2 M 2 v ]O 2   [Formula 2]
in Formula 2, M 2 is one or more selected from the group consisting of W, Cu, Fe, Ba, V, Cr, Ti, Zr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and 0.9≤x≤1.5, 0.8≤y<1, 0<z≤0.15, 0<w1≤0.15, 0<w2≤0.15, 0≤v≤0.2, and 0<w1+w2<0.2.

4 . The positive electrode material of claim 1 , wherein the large-diameter particle is a lithium composite transition metal oxide in a form of a secondary particle.

5 . The positive electrode material of claim 1 , wherein the large-diameter particle is a lithium composite transition metal oxide having a nickel content of 80 atm % or greater in all transition metals.

6 . The positive electrode material of claim 5 , wherein the large-diameter particle is a lithium composite transition metal oxide represented by [Formula 1] below:
Li x [Ni y Co z M 1 w M 2 v ]O 2   [Formula 1]
in Formula 1, M 1 is one or more selected from Mn and Al, M 2 is one or more selected from the group consisting of W, Cu, Fe, Ba, V, Cr, Ti, Zr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and 0.9≤x≤1.5, 0.8≤y<1, 0<z≤0.15, 0<w<0.2, and 0≤v≤0.2.

7 . The positive electrode material of claim 1 , wherein the average particle diameter (D 50 ) of the small-diameter particles is 2 to 8 μm.

8 . The positive electrode material of claim 1 , wherein the average particle diameter (D 50 ) of the large-diameter particles is 10 to 20 μm.

9 . The positive electrode material of claim 1 , wherein the small-diameter particle and the large-diameter particle are included in a weight ratio of 1:9 to 5:5.

10 . A method for producing a positive electrode material, comprising:
mixing a transition metal precursor having a nickel content of 80 atm % or greater in all transition metals of the transition metal precursor with a lithium raw material to obtain a mixture, overfiring the mixture at a temperature of 800° C. to 850° C. to prepare a lithium composite transition metal oxide in a form of a single particle and containing rock salt phases having an average thickness of 10-30 nm formed on a surface thereof; and mixing the lithium composite transition metal oxide in the form of the single particle with a large-diameter particle having a greater average particle diameter (D 50 ) than the lithium composite transition metal oxide in the form of the single particle.

11 . The method of claim 10 , wherein the transition metal precursor and the lithium raw material are mixed wherein a molar ratio of lithium:transition metal is 1.05:1 to 1.1:1.

12 . A positive electrode comprising the positive electrode material of claim 1 .

13 . A lithium secondary battery comprising the positive electrode of claim 12 .

Assignees

• Lg Chemical Ltd

Inventors

• Han Jung Min
• Lee Dong Hun
• Park Sung Bin
• Cho Hyung Man
• Hwang Jin Tae
• Jung Wang Mo

Classifications

• C01G53/50

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

• H01M10/052

  Li-accumulators · CPC title

• C01P2004/53

  bimodal size distribution · CPC title

• H01M4/364 Primary

  as mixtures · 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