Cathode active material, preparation method thereof, cathode including the same, and secondary battery

Patent metadata

Field	Value
Publication number	US-12009519-B2
Application number	US-202117482684-A
Country	US
Kind code	B2
Filing date	Sep 23, 2021
Priority date	Apr 20, 2021
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

A cathode active material includes a compound represented by Formula 1:

Li x (Co 1−y M y ) z (P 2 O 7 ) 4   Formula 1
wherein in Formula 1, 5≤x≤7, 0.01≤y≤0.1, and 4≤z≤6, and M is a Group 3 to 11 element belonging to 5th and 6th periods in the Periodic Table of the elements, or a combination thereof.

First claim

What is claimed is:

1. A cathode active material comprising a compound
represented by Formulas 2a to 2r:
Li x (Co 1−y Nb y ) z (P 2 O 7 ) 4   Formula 2a

wherein in Formula 2a, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Mo y ) z (P 2 O 7 ) 4   Formula 2b

wherein in Formula 2b, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Ta y ) z (P 2 O 7 ) 4   Formula 2c

wherein in Formula 2c, 5.5≤x≤6.5, 0.01≤00.05, and 4.8≤z≤5.2,
Li x (Co 1−y W y ) z (P 2 O 7 ) 4   Formula 2d

wherein in Formula 2d, 5.5≤x≤6.5, 0.01≤00.05, and 4.8≤z≤5.2,
Li x (Co 1−y Y y ) z (P 2 O 7 ) 4   Formula 2e

wherein in Formula 2e, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y La y ) z (P 2 O 7 ) 4   Formula 2f

wherein in Formula 2f, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Zr y ) z (P 2 O 7 ) 4   Formula 2g

wherein in Formula 2g, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Hf y ) z (P 2 O 7 ) 4   Formula 2h

wherein in Formula 2h, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y TC y ) z (P 2 O 7 ) 4   Formula 2i

wherein in Formula 2i, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Re y ) z (P 2 O 7 ) 4   Formula 2j

wherein in Formula 2j, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Ru y ) z (P 2 O 7 ) 4   Formula 2k

wherein in Formula 2k, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y O s ) z (P 2 O 7 ) 4   Formula 2l

wherein in Formula 2l, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Rh y ) z (P 2 O 7 ) 4   Formula 2m

wherein in Formula 2m, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Ir y ) z (P 2 O 7 ) 4   Formula 2n

wherein in Formula 2n, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Pd y ) z (P 2 O 7 ) 4   Formula 2o

wherein in Formula 2o, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Pt y ) z (P 2 O 7 ) 4   Formula 2p

wherein in Formula 2p, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2,
Li x (Co 1−y Ag y ) z (P 2 O 7 ) 4   Formula 2q

wherein in Formula 2q, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2, or
Li x (Co 1−y Au y ) z (P 2 O 7 ) 4   Formula 2r

wherein in Formula 2r, 5.5≤x≤6.5, 0.01≤y≤0.05, and 4.8≤z≤5.2.

2. The cathode active material of claim 1 ,
wherein the compound of Formulas 2a-2r has a crystal structure belonging to a triclinic crystal system.

3. The cathode active material of claim 1 ,
wherein the compound of Formulas 2a-2r has a crystal structure belonging to a P−1 space group.

4. The cathode active material of claim 1 ,
wherein the compound of Formulas 2a-2r has a band gap of about 0.1 electron volt to about 2.0 electron volts.

5. The cathode active material of claim 1 ,
wherein the compound of Formulas 2a-2r has an average discharge voltage of 4 volts or more.

6. The cathode active material of claim 1 ,
wherein, when analyzed by X-ray diffraction using Cu-Kα radiation, the compound represented by Formulas 2a-2r has a primary peak at a diffraction angle, 2θ, of 28.0°±1.0°, and a secondary peak at a diffraction angle, 2θ, of 33.5°±1.0°.

7. The cathode active material of claim 6 ,
wherein a ratio of an intensity of the secondary peak to an intensity of the primary peak, is greater than 0 and equal to or less than about 0.5.

8. A cathode comprising: a cathode current collector and a cathode active material layer on a surface of the cathode current collector, the cathode active material layer comprising the cathode active material of claim 1 .

9. A secondary battery comprising:
a cathode; an anode; and an electrolyte between the cathode and the anode,
wherein the cathode comprises the cathode active material of claim 1 .

10. The secondary battery of claim 9 ,
wherein the secondary battery is a multi-layer ceramic battery or a thin-film battery comprising the cathode active material.

11. The secondary battery of claim 10 ,
wherein the multi-layer ceramic battery comprises:
a plurality of cathode layers, at least one of the plurality of the cathode layers comprising the cathode active material;
a plurality of anode layers alternately arranged between the plurality of cathode layers; and
a plurality of solid electrolyte layers alternately arranged between the plurality of cathode layers and the plurality of anode layers.

12. The secondary battery of claim 9 ,
wherein the electrolyte comprises an oxide solid electrolyte.

13. The secondary battery of claim 9 ,
wherein the anode comprises a lithium metal phosphate oxide, a lithium metal oxide, a metal oxide, or a combination thereof.

14. The secondary battery of claim 10 ,
wherein the multi-layer ceramic battery is a sintered product.

15. A method of preparing a cathode active material of claim 1 , the method comprising:
mixing a cobalt precursor, a lithium precursor, a phosphorus precursor, and an M precursor to prepare a precursor mixture; and
heat-treating the precursor mixture to form the cathode active material of claim 1 .

16. The method of claim 15 ,
wherein the heat-treating of the precursor mixture is performed at about 500° C. to about 1000° C. for about 1 hour to about 48 hours.

17. The method of claim 15 ,
wherein the heat-treating comprises heat-treating the precursor mixture in an oxidative atmosphere or in an inert atmosphere.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Joonhee
• Ma Sangbok
• Ka Jonghoon

Classifications

• H01M10/0562

  Solid materials · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/0471 Primary

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

• C01P2002/74

  by peak-intensities or a ratio thereof only · CPC title

• C01P2002/72

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