Composite cathode active material for lithium battery, cathode for lithium battery including the same, and lithium battery including the cathode

Patent metadata

Field	Value
Publication number	US-2017018767-A1
Application number	US-201615207885-A
Country	US
Kind code	A1
Filing date	Jul 12, 2016
Priority date	Jul 13, 2015
Publication date	Jan 19, 2017
Grant date	—

Abstract

A composite cathode active material for a lithium battery including: a lithium composite oxide; and a coating layer including a metal oxide and a lithium fluoride, (LiF) wherein the coating layer is disposed on at least a portion of a surface of the lithium composite oxide.

First claim

What is claimed is:

1 . A composite cathode active material for a lithium battery comprising:
a lithium composite oxide; and a coating layer comprising a metal oxide and a lithium fluoride, wherein the coating layer is disposed on at least a portion of a surface of the lithium composite oxide.

2 . The composite cathode active material of claim 1 , wherein a mole ratio of the metal oxide to the lithium fluoride is in a range of about 1:1 to about 1:6.

3 . The composite cathode active material of claim 1 , wherein a spinel phase is disposed between the lithium composite oxide and the coating layer.

4 . The composite cathode active material of claim 1 , wherein the coating layer is a single layer comprising a composite comprising the metal oxide and the lithium fluoride or a mixture comprising the metal oxide and the lithium fluoride.

5 . The composite cathode active material of claim 1 , wherein the metal oxide is at least one selected from Al 2 O 3 , Bi 2 O 3 , B 2 O 3 , ZrO 2 , MgO, Cr 2 O 3 , MgAl 2 O 4 , Ga 2 O 3 , SiO 2 , SnO 2 , CaO, SrO, BaO, Y 2 O 3 , TiO 2 , Fe 2 O 3 , (MoO 3 , MoO 2 , CeO 2 , La 2 O 3 , ZnO, and LiAlO 2 .

6 . The composite cathode active material of claim 1 , wherein the composite cathode active material does not have a peak between about 23 degrees two-theta to about 27 degrees two-theta, when analyzed by X-ray powder diffraction.

7 . The composite cathode active material of claim 1 , wherein the coating layer does not comprise AlF 3 .

8 . The composite cathode active material of claim 1 , wherein the coating layer consists of the metal oxide and the lithium fluoride.

9 . The composite cathode active material of claim 1 , wherein the composite cathode active material has a peak between about 72 electron volts to about 75 electron volts, and has a peak between about 683 electron volts to about 688 electron volts, when analyzed by X-ray photoelectron spectroscopy.

10 . The composite cathode active material of claim 1 , wherein a total amount of the metal oxide and the lithium fluoride is in a range of about 0.01 weight percent to about 10 weight percent, based on a total weight of the composite cathode active material.

11 . The composite cathode active material of claim 1 , wherein the lithium composite oxide comprises at least one selected from a layered oxide, an olivine oxide, and a spinel-phase oxide.

12 . The composite cathode active material of claim 1 , wherein the lithium composite oxide comprises at least one selected from compounds represented by Formulae 1 to 6:
Li a Ni x Co y Mn z M c O 2-e A e   Formula 1
wherein, in Formula 1,
1.0<a≦1.4, 0<x<1, 0≦y<1, 0<z<1, 0≦c<1, 0<x+y+z+c<1, and 0≦e<1;
M is at least one selected from V, Mg, Ga, Si, W, Mo, Fe, Cr, Cu, Zn, Ti, Al, and B; and
A is at least one anion element selected from F, S, Cl, and Br,
Li[Co 1-x M x ]O 2-a A a   Formula 2

wherein, in Formula 2,
0≦a≦0.1 and 0≦x≦0.1;
M is at least one metal selected from Mg, Al, Ni, Mn, Zn, Fe, Cr, Ga, Mo, and W; and
A is at least one anion element selected from F, S, Cl, and Br,
Li 1+a [Ni 1-x M x ]O 2-b A b   Formula 3

wherein, in Formula 3,
0.01≦a≦0.2, 0≦b≦0.1, and 0.01≦x≦0.5;
M is at least one metal selected from Mg, Al, Co, Mn, Zn, Fe, Cr, Ga, Mo, and W; and
A is at least one anion element selected from F, S, Cl, and Br,
Li 1+a [Mn 2-x M x ]O 4-b A b   Formula 4

wherein, in Formula 4,
0.01≦a≦0.15, 0≦b≦0.1, and 0≦x≦0.1; A is at least one anion element selected from F, S, Cl, and Br; and
M is at least one selected from Co, Ni, Cr, Mg, Al, Zn, Mo, and W,
LiM x Fe 1-x PO 4   Formula 5

wherein, in Formula 5,
M is at least one metal selected from Co, Ni, and Mn; and

0≦x≦1,
Li 1+a [Ni 0.5 Mn 1.5-x M x ]O 4-b A b   Formula 6

wherein, in Formula 6,
0.01≦a≦0.15, 0≦b≦0.1, and 0≦x≦0.1; A is at least one anion element selected from F, S, Cl, and Br; and
M is at least one metal selected from Co, Ni, Cr, Mg, Al, Zn, Mo, and W.

13 . The composite cathode active material of claim 1 , wherein the lithium composite oxide comprises at least one selected from compounds represented by Formula 7:
Li a Ni x Co y Mn z M c O 2-b A b   Formula 7
wherein, in Formula 7, 1.0<a≦1.4, 0<x<1, 0≦y<1, 0<z<1, 0≦c<1, 0<x+y+z+c<1, and 0≦b≦0.1; M is at least one selected from V, Mg, Ga, Si, W, Mo, Fe, Cr, Cu, Zn, Ti, Al, and B; and A is at least one anion element selected from F, S, Cl, and Br.

14 . The composite cathode active material of claim 1 , wherein a thickness of the coating layer is in a range of about 1 nanometer to about 1 micrometer.

15 . The composite cathode active material of claim 1 , wherein the coating layer is in the form of a continuous layer.

16 . The composite cathode active material of claim 1 , wherein the lithium composite oxide is at least one selected from Li 1.167 Ni 0.542 Co 0.083 Mn 0.20 O 2 , Li 1.130 Ni 0.565 Co 0.088 Mn 0.217 O 2 , Li 1.167 Ni 0.5 Co 0.125 Mn 0.208 O 2 , Li 1.130 Ni 0.522 Co 0.130 Mn 0.217 O 2 , Li 1.167 Ni 0.5 Co 0.1665 Mn 0.1665 O 2 , Li 1.130 Ni 0.522 Co 0.174 Mn 0.174 O 2 , Li 1.167 Ni 0.458 Co 0.083 Mn 0.292 O 2 , Li 1.130 Ni 0.478 Co 0.087 Mn 0.305 O 2 , Li 1.167 Ni 0.542 Co 0.083 Mn 0.208 O 1.99 F 0.01 , Li 1.130 Ni 0.565 Co 0.088 Mn 0.217 O 1.99 F 0.01 , and Li 1.167 Ni 0.5 Co 0.125 Mn 0.208 O 1.99 F 0.01 .

17 . The composite cathode active material of claim 1 , wherein the coating layer comprises a composite that includes Al 2 O 3 and LiF.

18 . A method of preparing a composite cathode active material for a lithium battery, the method comprising:
mixing a metal oxide precursor, a lithium composite oxide, a fluoride precursor, and a solvent to prepare a reaction product; drying the reaction product; and heat-treating the dried reaction product to prepare the composite cathode active material, wherein the composite cathode active material comprises a lithium composite oxide, and a coating layer comprising a metal oxide and a lithium fluoride, wherein the coating layer is disposed on at least a portion of a surface of the lithium composite oxide.

19 . The method of claim 18 , wherein the drying is performed at a temperature in a range of about 50° C. to about 100° C.

20 . The method of claim 18 , wherein the heat-treating is performed at a temperature in a range of about 400° C. to about 700° C. and in an inert gas atmosphere or in an oxidative gas atmosphere.

21 . The method of claim 18 , wherein the heat-treating is performed at a temperature in a range of about 450° C. to about 700° C. and in an inert gas atmosphere or in an oxidative gas atmosphere.

22 . The method of claim 18 , wherein the metal oxide precursor comprises at least one selected from an alkoxide, a sulfate, a nitrate, an acetate, a chloride, and a phosphate of at least one selected from aluminum, bismuth, boron, zirconium, magnesium, chrome, gallium, silicon, tin, calcium, strontium, barium, yttrium, titanium, iron, molybdenum, cerium, lanthanum, and zinc.

23 . The method of claim 18 , wherein the fluoride precursor comprises at least one selected from ammonium fluoride, ammonium hydrogen fluoride, cesium fluoride, potassium fluoride, and sodium fluoride.

24 . The method of claim 18 , wherein a washing process is not performed before the drying of the reacted product.

25 . The method of claim 18 , wherein a mole ratio of the metal oxide precursor to the fluoride p

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Park Kwangjin
• Park Junho
• Yoon Jaegu
• Hong Sukgi

Classifications

• C01P2002/54

  one element only · CPC title

• C01P2006/11

  Powder tap density · CPC title

• C01P2004/84

  one phase coated with the other · CPC title

• C01P2002/72

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

• H01M50/417

  Polyolefins · CPC title