Positive electrode active material for secondary battery, method of preparing the same, and lithium secondary battery including the positive electrode active material

Patent metadata

Field	Value
Publication number	US-12176535-B2
Application number	US-202318210427-A
Country	US
Kind code	B2
Filing date	Jun 15, 2023
Priority date	Jan 24, 2018
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

A positive electrode active material for a secondary battery includes a lithium composite transition metal oxide including nickel (Ni), cobalt (Co), and manganese (Mn), and a glassy coating layer formed on surfaces of particles of the lithium composite transition metal oxide, wherein, in the lithium composite transition metal oxide, an amount of the nickel (Ni) in a total amount of transition metals is 60 mol % or more, and an amount of the manganese (Mn) is greater than an amount of the cobalt (Co), and the glassy coating layer includes a glassy compound represented by Formula 1.

Li a M 1 b O c   [Formula 1]
wherein, M 1 is at least one selected from the group consisting of boron (B), aluminum (Al), silicon (Si), titanium (Ti), and phosphorus (P), and 1≤a≤4, 1≤b≤8, and 1≤c≤20.

First claim

The invention claimed is:

1. A positive electrode active material for a secondary battery, the positive electrode active material comprising:
a lithium composite transition metal oxide including nickel (Ni), cobalt (Co), and manganese (Mn), wherein the lithium composite transition metal oxide is in the form of a secondary particle comprising agglomerated primary particles; and a coating layer formed on a surface of the secondary particle and surfaces of the primary particles within the secondary particle,
wherein, in the lithium composite transition metal oxide, an amount of the nickel (Ni) in a total amount of transition metals is 60 mol % or more, and an amount of the manganese (Mn) is greater than an amount of the cobalt (Co), and
the coating layer comprises a compound represented by Formula 1:
Li a M 1 b O c   [Formula 1]

wherein, in Formula 1, M 1 is at least one selected from the group consisting of boron (B), aluminum (Al), silicon (Si), titanium (Ti), and phosphorus (P), and 1≤a≤4, 1≤b≤8, and 1≤c≤20;
wherein the positive electrode active material has a particle strength of 150 Mpa or more.

2. The positive electrode active material of claim 1 , wherein an amount of residual lithium by-products in the positive electrode active material is 1.0 wt % or less.

3. The positive electrode active material for a secondary battery of claim 1 , wherein the positive electrode active material has a particle strength of 200 MPa to 250 MPa.

4. The positive electrode active material for a secondary battery of claim 1 , wherein the coating layer comprises a lithium-boron-aluminum oxide.

5. The positive electrode active material for a secondary battery of claim 4 , wherein, in the coating layer, boron and aluminum are included at a ratio of 0.3 part by weight: 1 part by weight to 0.8 part by weight:1 part by weight.

6. The positive electrode active material for a secondary battery of claim 1 , wherein the lithium composite transition metal oxide is represented by Formula 2:
Li p Ni 1−(x1+y1+z1) Co x1 Mn y1 M 2 z1 M 3 q1 O 2   [Formula 2]

wherein, in Formula 2, M 2 is at least one element selected from the group consisting of aluminum (Al), zirconium (Zr), boron (B), tungsten (W), magnesium (Mg), cerium (Ce), hafnium (Hf), tantalum (Ta), titanium (Ti), strontium (Sr), barium (Ba), fluorine (F), phosphorus (P), sulfur(S) , and lanthanum (La), M 3 is at least one element selected from the group consisting of Al, Zr, Ti, Mg, Ta, niobium (Nb), molybdenum (Mo), W, and chromium (Cr), and 0.9≤p≤1.1, 0<x1≤0.4, 0<y1≤0.4, 0≤z1≤0.1, 0≤q1≤0.1, x1<y1, and 0<x1+y1+z1≤0.4.

7. The positive electrode active material for a secondary battery of claim 1 , wherein, in the lithium composite transition metal oxide, the amount of the nickel (Ni) in the total amount of the transition metals is 80 mol % or more.

8. The positive electrode active material for a secondary battery of claim 1 , wherein the coating layer is included in an amount of 0.02 part by weight to 0.2 part by weight based on 100 parts by weight of the lithium composite transition metal oxide.

9. The positive electrode active material for a secondary battery of claim 1 , wherein the coating layer is formed to a thickness of 20 nm to 100 nm.

10. A positive electrode for a secondary battery, the positive electrode comprising the positive electrode active material of claim 1 .

11. A lithium secondary battery comprising the positive electrode of claim 10 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Baek So Ra
• Kang Min Suk
• Lee Sang Wook
• Jung Wang Mo
• Lee Dong Hun
• Jeon Hye Lim
• Lho Eun Sol

Classifications

• C01B35/121

  of alkali metal · CPC title

• C01P2004/80

  Particles consisting of a mixture of two or more inorganic phases · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2006/80

  Compositional purity · CPC title

• C01G53/50

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