Composite cathode active material and secondary battery including the same

Patent metadata

Field	Value
Publication number	US-2018212233-A1
Application number	US-201815871245-A
Country	US
Kind code	A1
Filing date	Jan 15, 2018
Priority date	Jan 24, 2017
Publication date	Jul 26, 2018
Grant date	—

Abstract

A composite cathode active material including: a core particle; a first coating layer; and a second coating layer; wherein the core particle includes a cathode active material, the first and second coating layers cover a surface of the core particle, the first coating layer includes a first lithium-containing compound, wherein the first lithium-containing compound includes zirconium, niobium, titanium, aluminum, or a combination thereof, the second coating layer includes a second lithium-containing compound, wherein the second lithium-containing compound includes germanium, niobium, gallium, or a combination thereof, and the first lithium-containing compound is different from the second lithium-containing compound.

First claim

What is claimed is:

1 . A composite cathode active material comprising:
a core particle; a first coating layer; and a second coating layer,
wherein
the core particle comprises a cathode active material,
the first and second coating layers cover a surface of the core particle,
the first coating layer comprises a first lithium-containing compound, wherein the first lithium-containing compound comprises zirconium, niobium, titanium, aluminum, or a combination thereof,
the second coating layer comprises a second lithium-containing compound, wherein the second lithium-containing compound comprises germanium, niobium, and gallium, or a combination thereof, and
the first lithium-containing compound is different from the second lithium-containing compound.

2 . The composite cathode active material of claim 1 , wherein the first coating layer is disposed on the surface of the core particle, and the second coating layer is disposed on a surface of the first coating layer.

3 . The composite cathode active material of claim 1 , wherein the first lithium-containing compound comprises a lithium-containing oxide or a lithium-containing phosphorus oxide.

4 . The composite cathode active material of claim 1 , wherein the first lithium-containing compound comprises lithium zirconium oxide, lithium niobium oxide, lithium titanium oxide, lithium aluminum oxide, or a combination thereof.

5 . The composite cathode active material of claim 4 , wherein the lithium zirconium oxide comprises aLi 2 O—ZrO 2 where 0.1≤a≤2.

6 . The composite cathode active material of claim 1 , wherein the first lithium-containing compound comprises lithium zirconium phosphorus oxide or lithium titanium phosphorus oxide.

7 . The composite cathode active material of claim 1 , wherein the second lithium-containing compound comprises lithium germanium oxide, lithium niobium oxide, lithium gallium oxide, or a combination thereof.

8 . The composite cathode active material of claim 1 , wherein the first coating layer has a thickness ranging between about 1 nanometer and about 50 nanometers.

9 . The composite cathode active material of claim 1 , wherein a total thickness of the first coating layer and the second coating layer ranges between about 1 nanometer and about 500 nanometers.

10 . The composite cathode active material of claim 1 , wherein composite cathode active material comprises a plurality of core particles, and
wherein the core particles of the plurality of core particles have a mean particle diameter of about 10 micrometers or less.

11 . The composite cathode active material of claim 1 , wherein the core particle comprise a lithium transition metal oxide having a layered halite structure.

12 . The composite cathode active material of claim 1 , wherein the core particle comprises LiNi x Co y M z O 2 where M is aluminum or manganese, 0<x<1, 0<y<1,
and x+y+z=1.

13 . The composite cathode active material of claim 12 , wherein 0.5≤x<1.

14 . A cathode comprising the composite cathode active material according to claim 1 .

15 . A lithium secondary battery comprising:
the cathode according to claim 14 ; an anode; and an electrolyte between the cathode and the anode.

16 . The lithium secondary battery of claim 15 , wherein the lithium secondary battery comprises an all-solid-state lithium secondary battery, and the electrolyte comprises a sulfide solid electrolyte.

17 . The lithium secondary battery of claim 16 , wherein the sulfide solid electrolyte comprises sulfur, lithium, and phosphorus, silicon, boron, aluminum, germanium, zinc, gallium, indium, a halogen, or a combination thereof.

18 . The lithium secondary battery of claim 16 , wherein the sulfide solid electrolyte comprises lithium sulfide and silicon sulfide, phosphorus sulfide, boron sulfide, or a combination thereof.

19 . The lithium secondary battery of claim 16 , wherein the sulfide solid electrolyte comprises Li 2 S and P 2 S 5 .

20 . The lithium secondary battery of claim 16 , wherein the sulfide solid electrolyte is in a form of a particle.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Ito Seitaro
• Shiratsuchi Tomoyuki
• Aihara Yuichi
• Tsujimura Tomoyuki

Classifications

• H01M4/362 Primary

  Composites · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M2300/0068

  inorganic · CPC title

• H01M4/505

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

• H01M4/366 Primary

  as layered products · CPC title