Cathode active material for lithium secondary battery, cathode and lithium secondary battery comprising same, and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-11424438-B2
Application number	US-201916576290-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Dec 18, 2018
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A cathode active material for a lithium secondary battery, the cathode method including a core including a lithium metal oxide and a coating layer disposed on the surface and the inner grain boundaries of the core, wherein the coating layer includes a metal carbide, and a method of manufacturing the same.

First claim

What is claimed is:

1. A cathode active material for a lithium secondary battery comprising:
a nickel-based cathode active material core comprising a lithium metal oxide, and having inner grain boundaries; and
a coating layer disposed on a surface and the inner grain boundaries of the nickel-based cathode active material core;
wherein the coating layer comprises a metal carbide, and the metal carbide is contained in the coating layer in an amount of 0.5 to 2 mol %, and
the metal carbide comprises a carbide of at least one metal selected from a group consisting of nickel (Ni), cobalt (Co), titanium (Ti), iron (Fe), manganese (Mn), vanadium (V), copper (Cu), zirconium (Zr), zinc (Zn), molybdenum (Mo) and tungsten (W).

2. The cathode active material of claim 1 , wherein the lithium metal oxide comprises at least one compound represented by a formula selected from a group consisting of Li x Mn 1-y M′ y A 2 , Li x Mn 1-y M′ y O 2-z X z , Li x Mn 2 O 4-z X z , Li x Mn 2-y M′ y A 4 , Li x Co 1-y M′ y A 2 , Li x Co 1-y M′ y O 2-z X z , Li x Ni 1-y M′ y A 2 , Li x Ni 1-y M′ y O 2-z X z , Li x Ni 1-y Co y O 2-z X z , Li x Ni 1-y-z Co y M′ z A α , Li x Ni 1-y-z Co y M′ z O 2-α X α , Li x Ni 1-y-z Mn y M′ z A α , and Li x Ni 1-y-z Mn y M′ z O 2-α X α (where 0.95≤x≤1.1, 0≤y≤0.5, 0≤z≤0.5, and 0<α≤2),
wherein, M′ is at least one element selected from a group consisting of aluminum (Al), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), iron (Fe), magnesium (Mg), strontium (Sr), vanadium (V), ruthenium (Ru), tin (Sn), titanium (Ti), arsenic (As), molybdenum (Mo) and a rare earth element, A is an element selected from a group consisting of oxygen (O), fluorine (F), sulfur (S) and phosphorous (P), and X is an element selected from a group consisting of fluorine (F), sulfur (S) and phosphorus (P).

3. A lithium secondary battery, comprising:
a cathode comprising a cathode active material comprising a nickel-based cathode active material core comprising a lithium metal oxide and a coating layer disposed on a surface and inner boundaries of the nickel-based cathode active material core, wherein the coating layer comprises a metal carbide, and the metal carbide is contained in the coating layer in an amount of 0.5 to 2 mol % and the metal carbide comprises a carbide of at least one metal selected from a group consisting of nickel (Ni), cobalt (Co), titanium (Ti), iron (Fe), manganese (Mn), vanadium (V), copper (Cu), zirconium (Zr), zinc (Zn), molybdenum (Mo) and tungsten (W);
an anode; and
an electrolyte.

4. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of nickel (Ni).

5. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of cobalt (Co).

6. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of titanium (Ti).

7. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of iron (Fe).

8. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of manganese (Mn).

9. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of vanadium (V).

10. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of copper (Cu).

11. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of zirconium (Zr).

12. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of zinc (Zn).

13. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of molybdenum (Mo).

14. The cathode active material of claim 1 , wherein the metal carbide comprises a carbide of and tungsten (W).

15. A method of manufacturing the cathode active material for a lithium secondary battery according to claim 1 , the method comprising:
dry mixing the metal carbide with the core comprising the lithium metal oxide to prepare a mixture; and
forming the metal carbide coating layer on the surface and the inner grain boundaries of the core by heating the mixture.

16. The method of claim 15 , wherein the dry mixing comprises at least one selected from a group consisting of a planetary ball mill method, a low speed ball mill method, a high speed ball mill method, a hybridization method and a mechanofusion method.

17. The method of claim 15 , wherein the metal carbide is contained in the coating layer in an amount of 0.5 to 2 mol %.

18. The method of claim 15 , wherein a temperature for the heating is 600 to 700° C.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Lee Jieun
• Yeo Yeolmae
• Oh Seung-Min
• Park Sang Mok
• Lee Yoon Sung
• Kim Dongjun

Classifications

• C01G53/50

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

• H01M4/131 Primary

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

• H01M4/366 Primary

  as layered products · 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

• C01P2004/80

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