Nanorod-shaped cathode active material for lithium secondary battery, manufacturing method thereof, and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-10886532-B2
Application number	US-201816182738-A
Country	US
Kind code	B2
Filing date	Nov 7, 2018
Priority date	Nov 8, 2017
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

Provided are a cathode active material for a lithium secondary battery which is represented by general formula (1) below and has a nanorod shape, a manufacturing method thereof, and a lithium secondary battery including the same.

LiNi 1−x−y Mn x M y O 2   (1)

First claim

What is claimed is:

1. A cathode active material for a lithium secondary battery which is represented by general formula (1) below and has a nanorod shape:
LiNi 1−x−y Mn x M y O 2   (1)

wherein in general formula (1), M is at least one metal selected from a group consisting of Mg, Al, and Cr, 0.5<x<0.9, and 0<y≤0.1.

2. The cathode active material for a lithium secondary battery according to claim 1 , wherein an aspect ratio of the nanorod is in range of from 5 to 15.

3. A manufacturing method of a cathode active material for a lithium secondary battery, the method comprising:
mixing a nickel metal oxide, a metal oxide, and a solvent to prepare a first metal-mixed solution;
forming first nanoparticles of the first metal-mixed solution;
mixing the first nanoparticles formed as described above, a lithium metal oxide, and a solvent to prepare a second metal-mixed solution; and
performing a heat treatment to the second metal-mixed solution to form second nanoparticles, wherein the forming of the first nanoparticles is performed by a hydrothermal synthesis wherein the cathode active material for a lithium secondary battery is represented by general formula (1) below and has a nanorod shape:
LiNi 1−x−y Mn x M y O 2   (1)

wherein in general formula (1), M is at least one metal selected from a group consisting of Mg, Al, and Cr, 0.5<x<0.9, and 0<y≤0.

4. The manufacturing method of a cathode active material for a lithium secondary battery according to claim 3 , wherein the heat treatment is performed in range of from 400° C. to 800° C.

5. The manufacturing method of a cathode active material for a lithium secondary battery according to claim 3 , further comprising:
adding a pH adjuster to the first metal-mixed solution.

6. The manufacturing method of a cathode active material for a lithium secondary battery according to claim 5 , wherein the pH adjuster includes at least one aqueous solution selected from a group consisting of a citric acid aqueous solution, an acrylic acid aqueous solution, an ammonia aqueous solution, and a sodium hydroxide aqueous solution.

7. A lithium secondary battery comprising:
the cathode active material of claim 1 ;
an anode active material; and
an electrolyte.

Assignees

• Korea Basic Science Inst

Inventors

• Kim Jong Guk
• Kim Hae Jin
• Hong Won Gi
• Lee Jin Bae

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

• H01M4/505 Primary

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

• C01P2004/54

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