Method of preparing positive electrode active material for lithium secondary battery and positive electrode active material for lithium secondary battery prepared thereby

Patent metadata

Field	Value
Publication number	US-2019123350-A1
Application number	US-201716086563-A
Country	US
Kind code	A1
Filing date	Mar 27, 2017
Priority date	Mar 25, 2016
Publication date	Apr 25, 2019
Grant date	—

Abstract

The present invention relates to a method of preparing a positive electrode active material for a lithium secondary battery and the positive electrode active material for the lithium secondary battery prepared thereby, and more specifically, to a method of preparing a positive electrode active material for a lithium secondary battery, the method comprising doping or coating the positive electrode active material for the lithium secondary battery with a predetermined metal oxide, and the positive electrode active material for the lithium secondary battery which is prepared thereby and has a reduced amount of residual lithium.

First claim

1 . A method of producing a lithium nickel composite oxide represented by the following chemical formula 2 is provided, the method comprising the steps of:
i) producing a nickel composite oxide represented by the following chemical formula 1;
Ni 1−x−y M1 x M2 y (OH) 2   [Chemical Formula 1]

(M1 is one or more elements selected from the group consisting of Co and Mn, M2 is one or more elements selected from the group consisting of Al, Mn, Mg, Si, P and Ga, 0≤a≤0.3, 0≤x≤0.03, and 0≤y≤0.03) ii) washing the compound obtained in the step i) by adding to a washing solution. iii) drying the compound washed in the step ii); iv) mixing the compound dried in the step iii) with a lithium compound and a metal oxide including M3 (M3 is one or more elements selected from the group consisting of Al, B, Ba, Mg, Ce, Cr, F, Li, Mo, P, Sr, Ti and Zr, and M1, M2 and M3 are not all equal); and v) heating the compound mixed in the step iv); whereby a lithium nickel composite oxide represented by [Chemical Formula 2] Li 1+a Ni 1−x−y M1 x M2 y M3 z O 2 is produced, and in chemical formula 2, M1 is one or more elements selected from the group consisting of Co and Mn, M2 is one or more elements selected from the group consisting of Al, Mn, Mg, Si, P and Ga, 0≤a≤0.3, 0≤x≤0.03, 0≤y≤0.03, and 0≤z≤0.03.

2 . The method of claim 1 , wherein the washing solution of the step ii) includes one or more selected from the group consisting of distilled water, methanol, ethanol, 2-propanol, 1-butanol, ethylene glycol, polyvinyl alcohol (PVA), acetone, acetyl acetone, benzophenone, NaOH, NH 4 OH, LiOH, KOH, Mg(OH) 2 , and Ba(OH) 2 .

3 . The method of claim 1 , wherein the step iii) of drying the compound washed in the step ii) includes drying the washed compound at 50 to 300° C. in a depressurized atmosphere.

4 . The method of claim 1 , wherein the metal oxide including the M3 has a particle diameter of 5 μm or less in the step iv) of mixing the compound dried in the step iii), the lithium compound and the metal oxide including M3.

5 . The method of claim 1 , wherein the M3 is cerium, and the metal oxide including the M3 is CeO 2 .

6 . The method of claim 1 , wherein the M3 is Mg, and the metal oxide including the M3 is MgO.

7 . The method of claim 1 , wherein 0.001 to 10 parts by weight of the metal oxide including M3 is mixed with 100 parts by weight of the compound dried in the step iii) in the step iv) of mixing the compound dried in the step iii), the lithium compound and the metal oxide including M3.

8 . A lithium nickel composite oxide produced by claim 1 .

9 . The method of claim 1 , further comprising a step (vi) of washing the compound heated in the step v) by adding to a washing solution.

10 . The method of claim 9 , wherein the washing solution includes one or more selected from the group consisting of distilled water, methanol, ethanol, 2-propanol, 1-butanol, ethylene glycol, polyvinyl alcohol (PVA), acetone, acetyl acetone, benzophenone, NaOH, NH 4 OH, LiOH, KOH, Mg(OH) 2 , and Ba(OH) 2 .

11 . The method of claim 1 , further comprising:
a step vii) of mixing a lithium nickel composite oxide represented by the chemical formula 2 with a surface coating metal oxide including M4 (M4 is one or more a step vii) of mixing a lithium nickel composite oxide represented by the chemical formula 2 with a surface coating metal oxide including M4 (M4 is one or more elements selected from the group consisting of Al, B, Ba, Mg, Ce, Cr, F, Li, Mo, P, Sr, Ti and Zr); and a step viii) of heating the compound mixed in the step vii).

12 . The method of claim 11 , wherein the surface coating metal oxide including M4 has a particle diameter of 5 μm or less.

13 . The method of claim 11 , wherein the surface coating metal oxide including M4 is CeO 2 .

14 . A lithium nickel composite oxide produced by the method of claim 9 .

15 . The lithium nickel composite oxide of claim 14 , wherein the lithium nickel composite oxide has peaks which are detected within 2θ ranges of 28° to 29°, 45° to 50° and 55° to 60° in the X-ray diffraction (XRD).

16 . A lithium nickel composite oxide produced by the method of claim 11 .

17 . The lithium nickel composite oxide of claim 16 , wherein the lithium nickel composite oxide has peaks which are detected within 2θ ranges of 28° to 29°, 45° to 50° and 55° to 60° in the X-ray diffraction (XRD).

Assignees

• Ecopro Bm Co Ltd

Inventors

• Choi Moon Ho
• Shin Jong Seung
• Jeon Suk Yong
• Yu Hyun Jong
• Park Young Nam

Classifications

• 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

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01G53/50

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

• H01M4/505

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