Composite transition metal oxide-based precursor, preparing method thereof, and cathode active material using the same

Patent metadata

Field	Value
Publication number	US-2017317349-A1
Application number	US-201615356946-A
Country	US
Kind code	A1
Filing date	Nov 21, 2016
Priority date	Apr 29, 2016
Publication date	Nov 2, 2017
Grant date	—

Abstract

The present disclosure provides a novel composite transition metal oxide-based precursor, a preparing method thereof, and a cathode active material for a secondary battery prepared from the precursor. In the present disclosure, it is possible to enhance productivity and economic efficiency due to a high reaction yield during the synthesis of a cathode active material and to enhance the initial discharge capacity and lifespan characteristics of a secondary battery including a cathode active material by using an oxide-based precursor having a high oxygen fraction instead of a hydroxide-based precursor used as a precursor of a cathode active material in the related art.

First claim

What is claimed is:

1 . A composite transition metal oxide-based precursor represented by the following Chemical Formula 1:
Ni a Co b M′ c O x (1< x≦ 1.5)  [Chemical Formula 1]
in the formula, M′ is one or more selected from the group consisting of an alkali metal, an alkaline earth metal, a Group XIII element, a Group XIV element, a Group XV element, a Group XVI element, a Group XVII element, a transition metal, and a rare earth element, and
0.6≦ a< 1.0, 0≦ b≦ 0.4, 0≦ c≦ 0.4, a+b+c= 1.

2 . The composite transition metal oxide-based precursor of claim 1 , wherein M′ is one or more selected from the group consisting of Al, Mn, Zr, W, Ti, Mg, Sr, Ba, Ce, Hf, F, P, S, La, and Y.

3 . The composite transition metal oxide-based precursor of claim 1 , wherein the precursor is a primary particle or a secondary particle in which a plurality of primary particles is aggregated.

4 . The composite transition metal oxide-based precursor of claim 3 , wherein the primary particle has a flake-like or needle-like shape with an average particle diameter in a range of 0.01 to 0.8 μm, and a plurality of pore structures is present on the surface or inside thereof, and the secondary particle has an average particle diameter (D50) in a range of 3 to 30 μm.

5 . The composite transition metal oxide-based precursor of claim 1 , wherein the precursor has a tap density of 2.0 g/cc or more.

6 . The composite transition metal oxide-based precursor of claim 1 , wherein the precursor has a specific surface area in a range of 5 to 80 m 2 /g measured according to the nitrogen adsorption BET method.

7 . The composite transition metal oxide-based precursor of claim 1 , wherein in the precursor, a volume of pores in a range of 5 nm to 50 nm is in a range of 10 −3 to 10 −2 cm 3 /g·nm per weight of particles.

8 . A cathode active material prepared using the composite transition metal oxide-based precursor of claim 1 and a lithium precursor.

9 . The cathode active material of claim 8 , wherein nickel (Ni) content is 60% or more in the overall transition metals.

10 . A method for preparing the composite transition metal oxide-based precursor of claim 1 , the method comprising a step of oxidizing a composite transition metal hydroxide-based precursor represented by the following Chemical Formula 2:
Ni a Co b M′ c (OH) 2   [Chemical Formula 2]
in the formula, M′ is one or more selected from the group consisting of an alkali metal, an alkaline earth metal, a Group XIII element, a Group XIV element, a Group XV element, a Group XVI element, a Group XVII element, a transition metal, and a rare earth element, and
0.6≦ a< 1.0, 0≦ b≦ 0.4, 0≦ c≦ 0.4, a+b+c= 1.

11 . The method of claim 10 , wherein in the step of oxidizing,
(i) a heat treatment is performed under an oxygen atmosphere, (ii) an oxidizing agent is used, or (iii) both (i) and (ii) are applied.

12 . The method of claim 10 , wherein in the oxidizing, a heat treatment is performed in a range of 200 to 1,000° C. under an oxygen atmosphere at an oxygen concentration of 80% or more for 1 to 12 hours.

13 . The method of claim 11 , wherein the oxidizing agent is one or more selected from the group consisting of KMnO 4 , H 2 O 2 , Na 2 O 2 , FeCl 3 , CuSO 4 , CuO, PbO 2 , MnO 2 , HNO 3 , KNO 3 , K 2 Cr 2 O 7 , CrO 3 , P 2 O 5 , H 2 SO 4 , K 2 S 2 O 8 , a halogen, and C 6 H 5 NO 2 .

Assignees

• Lg Chemical Ltd

Inventors

• Ju Seo Hee
• Choi Kwon Young
• Ban Sung Ho
• Eom Jun Ho

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/052

  Li-accumulators · CPC title

• 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

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• C01G53/70

  containing rare earths, e.g. LaNiO3  (C01G53/68 takes precedence) · CPC title