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

Patent metadata

Field	Value
Publication number	US-11532815-B2
Application number	US-202117476673-A
Country	US
Kind code	B2
Filing date	Sep 16, 2021
Priority date	Feb 28, 2017
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

The present invention relates to a positive electrode active material for a lithium secondary battery which includes a lithium composite transition metal oxide including nickel (Ni), cobalt (Co), and manganese (Mn), wherein a portion of nickel (Ni) sites of the lithium composite transition metal oxide is substituted with tungsten (W), and an amount of a lithium tungsten oxide remaining on surfaces of lithium composite transition metal oxide particles is 1,000 ppm or less.

First claim

The invention claimed is:

1. A method of preparing a positive electrode active material for a lithium secondary battery, the method comprising:
preparing a metal solution including a nickel-containing raw material, a cobalt-containing raw material, a manganese-containing raw material, and a tungsten-containing raw material;
preparing a positive electrode active material precursor by a co-precipitation reaction of the metal solution;
mixing and sintering the positive electrode active material precursor and a lithium raw material to prepare a lithium composite transition metal oxide in which a portion of nickel sites is substituted with tungsten; and
washing the sintered lithium composite transition metal oxide to remove a lithium tungsten oxide remaining on a surface of the lithium composite transition metal oxide.

2. The method of claim 1 , wherein the tungsten-containing raw material comprises at least one of Na 2 WO 4 , WO 3 , or H 2 WO 4 .

3. The method of claim 1 , wherein the metal solution comprises the tungsten-containing raw material in an amount of 0.05 mol % to 0.5 mol % based on a total of the nickel-containing raw material, the cobalt-containing raw material, the manganese-containing raw material, and the tungsten-containing raw material.

4. The method of claim 1 , wherein the positive electrode active material precursor is represented by Formula 2:
Ni 1−x2−y2−z2 W z2 Co x2 M 1 y2 (OH) 2   Formula 2

wherein, in Formula 2, 0<x 2 ≤0.2, 0<y 2 ≤0.2, and 0<z 2 ≤0.2, and M1 comprises at least one of Mn or Al.

5. The method of claim 4 , wherein, in Formula 2, 0<x 2 +y 2 +z 2 ≤0.2 is satisfied.

6. The method of claim 1 , wherein a sintering temperature is in a range of 700° C. to 900° C.

7. The method of claim 1 , wherein the washing is performed in a temperature range of −10° C. to 30° C.

8. The method of claim 1 , wherein the lithium composite transition metal oxide contains tungsten in an amount of 10 ppm to 5,000 ppm in a crystal structure.

9. The method of claim 1 , wherein an amount of the lithium tungsten oxide remaining on a surface of a lithium composite transition metal oxide particle after the washing is 1,000 ppm or less.

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Kim Ji Hye
• Park Byung Chun
• Baek So Ra
• Yoo Tae Gu
• Jung Wang Mo

Classifications

• C01P2004/54

  Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• Y02E60/50

  Fuel cells · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/364

  as mixtures · CPC title