Method of preparing positive electrode active material for secondary battery and secondary battery using the same

Patent metadata

Field	Value
Publication number	US-11437609-B2
Application number	US-201816615527-A
Country	US
Kind code	B2
Filing date	Oct 22, 2018
Priority date	Oct 20, 2017
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

A method of preparing a positive electrode active material includes forming a tungsten-doped lithium transition metal oxide, and washing the lithium transition metal oxide, wherein, in the washing, a hydroxide-based compound is added to a washing liquid during the washing, a positive electrode including a positive electrode active material prepared according to the method, and a lithium secondary battery including the positive electrode.

First claim

The invention claimed is:

1. A method of preparing a positive electrode active material comprising:
forming a tungsten-doped lithium transition metal oxide; and
washing the tungsten-doped lithium transition metal oxide with a washing liquid,

wherein, in the washing, a hydroxide-based compound is added to the washing liquid during the washing,
wherein the washing comprises:
primarily stirring after adding the tungsten-doped lithium transition metal oxide to the washing liquid, and
adding the hydroxide-based compound to the washing liquid and secondarily stirring after the primarily stirring.

2. The method of claim 1 , wherein the hydroxide-based compound comprises aluminum hydroxide (Al(OH) 3 ), magnesium hydroxide (Mg(OH) 2 ), cobalt hydroxide (Co(OH) 2 ), calcium hydroxide (Ca(OH) 2 ), barium hydroxide (Ba(OH) 2 ), or strontium hydroxide (Sr(OH) 2 ).

3. The method of claim 1 , wherein the hydroxide-based compound is added in an amount such that a weight ratio of tungsten doped in the lithium transition metal oxide to metal cations of the hydroxide-based compound is in a range of 1:0.3 to 1:0.6.

4. The method of claim 1 , wherein, in the secondarily stirring, metal cations of the hydroxide-based compound and tungstate anions dissolved from the tungsten-doped lithium transition metal oxide form a coating portion on surfaces of particles of the tungsten-doped lithium transition metal oxide.

5. The method of claim 1 , further comprising drying and heat treating the tungsten-doped lithium transition metal oxide after the washing.

6. The method of claim 5 , wherein a heat treatment temperature is in a range of 250° C. to 600° C.

7. The method of claim 1 , wherein the tungsten-doped lithium transition metal oxide comprises nickel (Ni), cobalt (Co), or manganese (Mn).

8. The method of claim 7 , wherein the tungsten-doped lithium transition metal oxide comprises transition metal cations of nickel (Ni), cobalt (Co), and manganese (Mn), and Ni is included in an amount of 80 mol % or more based on a total amount of transition metals.

9. The method of claim 1 , wherein the forming of the tungsten-doped lithium transition metal oxide comprises
mixing a lithium compound, a transition metal precursor, and a tungsten doping source to form a mixture, and
sintering the mixture to prepare the tungsten-doped lithium transition metal oxide.

10. A positive electrode comprising a positive electrode active material prepared according to claim 1 .

11. A lithium secondary battery comprising the positive electrode of claim 10 , a negative electrode, a separator disposed between the positive electrode and the negative electrode, and an electrolyte.

12. The lithium second battery of claim 11 , wherein the positive electrode active material of the positive electrode has a tungsten content of 1700 ppm to 3440 ppm.

13. The positive electrode of claim 10 , wherein the positive electrode active material has a tungsten content of 1700 ppm to 3440 ppm.

Assignees

• Lg Chemical Ltd

Inventors

• Baek Hyeon Hui
• Ban Sung Ho
• Eom Jun Ho
• Park Na Ri

Classifications

• H01M4/505 Primary

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

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• C01P2006/40

  Electric properties · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title