Lithium metal oxide particles coated with a mixture of the elements of the core material and one or more metal oxides

Patent metadata

Field	Value
Publication number	US-9859550-B2
Application number	US-201314650972-A
Country	US
Kind code	B2
Filing date	Nov 12, 2013
Priority date	Dec 14, 2012
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A lithium metal oxide powder for use as a cathode material in a rechargeable battery, consisting of a core material and a surface layer, the core having a layered crystal structure consisting of the elements Li, a metal M and oxygen, wherein the Li to M molar ratio is between 0.98 and 1.01, and preferably between 0.99 and 1.00, wherein the metal M has the formula M=Co 1-a M′ a , with 0≦a≦0.05, wherein M′ is either one or more metals of the group consisting of Al, Ga and B; and the surface layer consisting of a mixture of the elements of the core material and inorganic N- and N′-based oxides, wherein N is either one or more metals of the group consisting of Mg, Ti, Fe, Cu, Ca, Ba, Sn, Sb, Na, Zn, and Si; and wherein N′ is either one or more metals of the group consisting of Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Sc, Ce, Pr, Nd, Gd, Dy, and Er.

First claim

The invention claimed is:

1. A lithium metal oxide powder for use as a cathode material in a rechargeable battery, comprising a core material and a surface layer,
the core material having a layered crystal structure comprising the elements Li, a metal M and oxygen, wherein the Li to M molar ratio is between 0.98 and 1.01, wherein the metal M has the formula M=Co 1-a M′ a , with 0≦a≦0.05, and wherein M′ consists of Al, the Al content being between 0.1 and 1 mol %; and
the surface layer comprising a mixture of Li, O, Co, Al, inorganic N-based oxides and inorganic N′-based oxides, wherein N consists of Mg and Ti, the Mg content being between 0.1 and 1 mol % and the Ti content being between 0.1 and 0.5 mol %, and wherein N′ is selected from the group consisting of Zr, Nd, Er and Nb, the N′ content being between 0.1 and 1 mol %.

2. The lithium metal oxide powder of claim 1 , having a mean particle size D50 of at least 5 μm.

3. The lithium metal oxide powder of claim 1 , wherein a thickness of the surface layer is less than 100 nm.

4. The lithium metal oxide powder of claim 1 , wherein the surface layer further comprises less than 2000 ppm of one or more of LiF, Li 3 PO 4 and Li 2 SO 4 .

5. The lithium metal oxide powder of claim 1 , wherein the metal M in the core is diamagnetic.

6. The lithium metal oxide powder of claim 5 , wherein in the core, Li occupies a crystallographic site surrounded by trivalent diamagnetic metals.

7. The lithium metal oxide powder of claim 1 , having a pressed density of at least 3.40 g/cm 3 .

8. The lithium metal oxide powder of claim 1 , having a reversible electrode capacity of at least 200 mAh/g when used as an active component in a cathode which is cycled between 3.0 and 4.6 V vs. Li + /Li at a discharge rate of 0.1 C.

9. The lithium metal oxide powder of claim 8 , having a 1 C rate capacity fading value below 60%.

10. The lithium metal oxide powder of claim 1 , having a total base content of less than 50 μmol/g.

11. The lithium metal oxide powder of claim 1 , having a carbon content less than 50 ppm.

12. The lithium metal oxide powder of claim 1 , having an electrical conductivity less than 10 −4 S/cm.

13. The lithium metal oxide powder of claim 1 , wherein the surface layer is substantially free from lithium salts.

14. The lithium metal oxide powder of claim 1 , having a bimodal particle shape distribution where a small particle size fraction has a D50≦5 μm and is between 3 to 20 Vol %, and where a large particle size fraction has a D50≧12 μm.

15. The lithium metal oxide powder of claim 1 , having a bimodal particle shape distribution wherein a ratio of the mode of a small particle size fraction and a mode of a large particle size fraction is smaller than 1/3.

16. The lithium metal oxide powder of claim 1 , wherein the core material is substantially free from oxygen vacancies and from Li substitution for M in MO 2 layers of the layered crystal structure.

17. The lithium metal oxide powder of claim 1 , wherein the core material is substantially free from Co 2+ , Co 3+ , and Co 4+ .

18. A method for manufacturing the lithium metal oxide powder of claim 1 , the metal M having the formula M=Co 1-a M′ a , with 0≦a≦0.05, comprising:
providing a first mixture of a first Co- or Co and M′-comprising precursor powder and a first Li-comprising precursor powder, the first mixture having a Li to metal molar ratio>1.01,
sintering the first mixture in an oxygen comprising atmosphere at a temperature T 1 of at least 600° C., thereby obtaining a Li-enriched lithium metal oxide compound,
providing a second Co- or Co and M′-comprising precursor powder, and
mixing the Li-enriched lithium metal oxide compound and the second Co- or Co and M′-comprising precursor powder, thereby obtaining a second mixture wherein the Li to M molar ratio is between 0.98 and 1.01, and
sintering the second mixture in an oxygen comprising atmosphere at a temperature T 2 of at least 600° C.

19. A method for manufacturing the lithium metal oxide powder of claim 1 comprising:
providing a first mixture of a first Co- or Co and M′-comprising precursor powder and a first Li-comprising precursor powder, the first mixture having a Li to M metal molar ratio >1.01,
sintering the first mixture in an oxygen comprising atmosphere at a temperature T 1 of at least 600° C., thereby obtaining a Li-enriched lithium metal oxide compound,
providing a second Co- or Co and M′-comprising precursor powder,
mixing the Li-enriched lithium metal oxide compound and the second Co- or Co and M′ comprising precursor powder, thereby obtaining a second mixture wherein the Li to M molar ratio is between 0.98 and 1.01 and
sintering the second mixture in an oxygen comprising atmosphere at a temperature T 2 of at least 600° C.;

wherein one or more of the first Co- or Co and M′-comprising, the first Li-comprising, and the second Co- or Co and M′-comprising precursor powders further comprises at least one element selected from the group consisting of Mg and Ti; and wherein one or more of the first Co- or Co and M′-comprising, the first Li-comprising, and the second Co- or Co and M′-comprising precursor powders further comprises at least one metal selected from the group consisting of Zr, Nd, Er, and Nb.

20. A method for manufacturing the lithium metal oxide powder of claim 1 , comprising:
providing a first mixture of a first Co- or Co and M′-comprising precursor powder and a first Li-comprising precursor powder, the first mixture having a Li to M metal molar ratio >1.01,
sintering the first mixture in an oxygen comprising atmosphere at a temperature Ti of at least 600° C., thereby obtaining a Li-enriched lithium metal oxide compound,
mixing the Li-enriched lithium metal oxide compound with an oxide or a salt of at least one metal of the group consisting of Zr, Nd, Fr, and Nb, thereby obtaining a second mixture,
providing a second Co- or Co and M′-comprising precursor powder, and
mixing second mixture and the second Co- or Co and M′-comprising precursor powder, thereby obtaining a third mixture wherein the Li to M molar ratio is between 0.98 and 1.01, and
sintering the third mixture in an oxygen comprising atmosphere at a temperature T 2 of at least 600° C.,

wherein one or more of the first Co- or Co and M′-comprising, the first Li-comprising, and the second Co- or Co and M′-comprising precursor powders further comprises at least one element selected from the group consisting of Mg and Ti.

21. The method according to claim 19 , wherein the step of providing a second Co- or Co and M′-comprising precursor powder comprises the substeps of:
providing a third Co- or Co and M′-comprising precursor powder,
providing a second Li-comprising precursor powder, and
mixing quantities of the third Co- or Co and M′-comprising precursor powder and the second Li-comprising precursor powder so as to obtain the second Co- or Co and M′-comprising precursor powder having a Li to metal molar ratio of less than 0.9, wherein one or both of the third Co- or Co and M′-comprising and the second Li-comprising precursor powders further comprises at least one element selected from the group consisting of Mg and Ti; and wherein one or both of the third Co- or Co and M′-comprising and the second Li-comprising precursor powders further comprises at least one metal selected from the group consisting of Zr, Nd, Er, and Nb.

22. The method according to claim 21 , wherein one or more of the first, second and third M′-comp

Assignees

• Umicore Nv
• Umicore Korea Ltd

Inventors

• Blangero Maxime
• Kim Kyubo
• Choi Da-In

Classifications

• C01G51/42 Primary

  containing alkali metals, e.g. LiCoO2 · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• C01P2002/72

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

• C01P2006/40

  Electric properties · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title