Cobalt oxide for lithium secondary battery, preparing method thereof, lithium cobalt oxide for lithium secondary battery formed from the cobalt oxide, and lithium secondary battery including positive electrode comprising the lithium cobalt oxide

Patent metadata

Field	Value
Publication number	US-2020203726-A1
Application number	US-201716333195-A
Country	US
Kind code	A1
Filing date	Sep 5, 2017
Priority date	Sep 13, 2016
Publication date	Jun 25, 2020
Grant date	—

Abstract

Provided are a cobalt oxide (Co3O4) for a lithium secondary battery, having an average particle diameter (D50) of about 14 μm to about 19 μm and a tap density of about 2.1 g/cc to about 2.9 g/cc, a method of preparing the cobalt oxide, a lithium cobalt oxide for a lithium secondary battery prepared from the cobalt oxide, and a lithium secondary battery including a cathode including the lithium cobalt oxide.

First claim

1 . A cobalt oxide (Co 3 O 4 ) for a lithium secondary battery, the cobalt oxide having an average particle diameter (D50) of about 14 μm to about 19 μm and a tap density of about 2.1 g/cc to about 2.9 g/cc.

2 . The cobalt oxide of claim 1 , wherein a peak of an additional CoO phase appears at a diffraction angle 2θ of about 41° to about 44° in an X-ray diffraction spectrum of the cobalt oxide.

3 . The cobalt oxide of claim 1 , wherein the cobalt oxide comprises an additional CoO phase, and an amount of the additional CoO phase is from about 0.5 mole % to about 2 mole % based on a total amount 100 mol % of the cobalt oxide.

4 . A method of preparing a cobalt oxide for a lithium secondary battery, the method comprising:
reacting a mixture comprising a cobalt precursor, a precipitant, and a solvent at a temperature of about 40° C. to about 60° C. to obtain a cobalt carbonate; and thermally treating the cobalt carbonate under an oxidizing gas atmosphere to obtain the cobalt oxide according to claim 1 .

5 . The method of claim 4 , wherein the thermal treatment is performed at a temperature of about 800° C. to about 1,000° C.

6 . The method of claim 4 , wherein the precipitant is at least one selected from ammonium bicarbonate (NH 4 HCO 3 ), sodium carbonate (Na 2 CO 3 ), and sodium bicarbonate (NaHCO 3 ).

7 . The method of claim 4 , wherein, in the reacting of the mixture, the mixture has a pH of about 7 to about 8.

8 . A lithium cobalt oxide for a lithium secondary battery, the lithium cobalt oxide being a compound represented by Formula 1 and having a pellet density of about 4.0 g/cc to about 4.2 g/cc and an average particle diameter (D50) of about 23 μm to about 28 μm:
Li a CO b O c   [Formula 1]

wherein, in Formula 1, 0.9≤a≤1.1, 0.98≤b≤1.00, and 1.95≤c≤2.1 are satisfied.

9 . The lithium cobalt oxide of claim 8 , comprising at least one selected from magnesium (Mg), calcium (Ca), strontium (Sr), titanium (Ti), zirconium (Zr), boron (B), aluminum (Al), and fluorine (F).

10 . The lithium cobalt oxide of claim 8 , wherein the lithium cobalt oxide has a particle diameter (D10) of about 10 μm to about 12 μm, and a particle diameter (D90) of about 35 μm to about 45 μm.

11 . A lithium secondary battery comprising a cathode including the lithium cobalt oxide according to claim 8 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Park Junseok
• Kwon Seonyoung
• Kim Youngki
• Kim Jihyun
• Park Dohyung
• Park Sooyoun

Classifications

• C01P2006/11

  Powder tap density · CPC title

• C01P2004/51

  Particles with a specific particle size distribution · CPC title

• C01P2002/72

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

• C01P2002/52

  containing elements as dopants · CPC title

• C01G51/42

  containing alkali metals, e.g. LiCoO2 · CPC title