Composite cathode active material, method of preparing the composite cathode active material, and cathode and lithium battery each including the composite cathode active material

Patent metadata

Field	Value
Publication number	US-9601761-B2
Application number	US-201414261725-A
Country	US
Kind code	B2
Filing date	Apr 25, 2014
Priority date	Jun 24, 2013
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A composite cathode active material, a method of preparing the composite cathode active material, a cathode including the composite cathode active material, and a lithium battery including the cathode. The composite cathode active material includes a lithium intercalatable material; and a garnet oxide, wherein an amount of the garnet oxide is about 1.9 wt % or less, based on a total weight of the composite cathode active material.

First claim

What is claimed is:

1. A composite cathode active material comprising:
a core and a shell disposed on at least a portion of the core,
wherein the core comprises a lithium intercalatable material and
the shell comprises a garnet oxide,
wherein an amount of the garnet oxide is less than 1.9 weight percent, based on a total weight of the composite cathode active material,
wherein the core comprises a compound represented by Formula 4:
Li 2−x−y−z Ma x Mb y Mc z O 2+d   Formula 4

wherein x+y+z≦1; 0<x<1, 0<y<1, 0<z<1, and 0≦d≦0.1, and
Ma, Mb, and Mc are each independently at least one metal of Mn, Co, Ni, or Al.

2. The composite cathode active material of claim 1 , wherein the shell and the core form a mechanochemical bond.

3. The composite cathode active material of claim 1 , wherein the garnet oxide is represented by Formula 1 below:
L 5+x E 3 (Me z M 2−z )O d   Formula 1

wherein
L comprises at least one of a monovalent cation and a bivalent cation, wherein L comprises Li,
E comprises a monovalent cation and a trivalent cation,
Me and M each independently comprise a trivalent, a 4-valent, a 5-valent, or a 6-valent cation,
0<x≦3, 0≦z≦2, and 0<d≦12,
O is optionally substituted with at least one of a 5-valent, a 6-valent, or a 7-valent anion.

4. The composite cathode active material of claim 1 , wherein the garnet oxide is represented by Formula 2:
Li 5+x La 3 (Zr z A 2−z )O 12   Formula 2

wherein
A comprises at least one of Sc, Ti, V, Y, Nb, Hf, Ta, Al, Si, Ga, or Ge,
0<x≦3, and 0≦z≦2.

5. The composite cathode active material of claim 1 , wherein the garnet oxide comprises at least one of Li 7 La 3 Zr 2 O 12 , Li 6.75 La 3 (Zr 1.75 , Nb 0.25 )O 12 , Li 7.5 Rb 0.25 La 2.75 Zr 2 O 12 , Li 8 Rb 0.5 La 2.5 Zr 2 O 12 , Li 9 RbLa 2 Zr 2 O 12 , Li 7.125 Rb 0.0625 La 2.9375 Zr 2 O 12 , Li 6 SrLa 2 Ta 2 O 12 , or Li 7.125 K 0.0625 La 2.9375 Zr 2 O 12 .

6. The composite cathode active material of claim 1 , wherein the shell further comprises a carbonaceous material.

7. The composite cathode active material of claim 6 , wherein the carbonaceous material comprises at least one of a carbon nanotube, a carbon nanofiber, graphene, graphite, an expanded graphite, a carbon nanopowder, a hard carbon, or a soft carbon.

8. The composite cathode active material of claim 1 , wherein the core comprises a compound represented by Formula 5:
Li 2−x−y−z Ni x Co y Mn z O 2+d   Formula 5

wherein x+y+z≦1; 0<x<1, 0<y<1, 0<z<1, and 0≦d≦0.1.

9. A cathode comprising the composite cathode active material of claim 1 .

10. A lithium battery comprising the cathode of claim 9 .

11. A method of preparing a composite cathode active material, the method comprising:
contacting a lithium intercalatable material and a garnet oxide to form a shell comprising the garnet oxide disposed on a core comprising the lithium intercalatable material to prepare the composite cathode active material,
wherein an amount of the garnet oxide is less than 1.9 weight percent, based on a total weight of the composite cathode active material,
wherein the core comprises a compound represented by Formula 4:
Li 2−x−y−z Ma x Mb y Mc z O 2+d   Formula 4

wherein x+y+z≦1, 0<x<1, 0<y<1, 0<z<1, and 0≦d≦0.1, and
Ma, Mb, and Mc are each independently at least one metal of Mn, Co, Ni, or Al.

12. The method of claim 11 , wherein the contacting comprises a dry coating method.

13. The method of claim 12 , wherein the dry coating method comprises at least one of ball milling, a hybridization method, or a mechanofusion method.

14. The composite cathode active material of claim 1 , wherein the amount of the garnet oxide is greater than 0 to about 1.5 wt %.

15. The composite cathode active material of claim 1 , wherein the amount of the garnet oxide is greater than 0 to about 1.0 wt %.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Mun Jun-Young
• Lee Jae-Myung
• Kim Gue-Sung
• Kang Yoon-Sok
• Kim Myung-Hoon
• Park Jun-Ho
• Park Jin-Hwan
• Yoon Jae-Gu
• Choi Byung-Jin

Classifications

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title