Double-shell core lithium nickel manganese cobalt oxides

Patent metadata

Field	Value
Publication number	US-9614226-B2
Application number	US-201013505582-A
Country	US
Kind code	B2
Filing date	Oct 19, 2010
Priority date	Nov 5, 2009
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A lithium transition metal oxide powder for use in a rechargeable battery is disclosed, where the surface of the primary particles of said powder is coated with a first inner and a second outer layer, the second outer layer comprising a fluorine-containing polymer, and the first inner layer consisting of a reaction product of the fluorine-containing polymer and the primary particle surface. An example of this reaction product is LiF, where the lithium originates from the primary particles surface. Also as an example, the fluorine-containing polymer is either one of PVDF, PVDF-HFP or PTFE.

First claim

The invention claimed is:

1. A rechargeable battery comprising:
a cathode comprising a primary particle of lithium transition metal oxide powder, wherein a surface of the primary particle is coated with an inner layer and an outer layer,
the outer layer comprises a partially decomposed fluorine-containing polymer,
the inner layer comprises LiF with a thickness of at least 0.5 nm, and
the surface of the primary particle is Li depleted,
wherein the partially decomposed fluorine-containing polymer and the LiF are produced from the heating of a mixture of a bare lithium transition metal oxide powder and the fluorine-containing polymer at a temperature between 50° C. and 140° C. above the melting temperature of the fluorine-containing polymer.

2. The rechargeable battery of claim 1 , wherein the fluorine-containing polymer is selected from the group consisting of PVDF, PVDF-HFP, and PTFE.

3. The rechargeable battery of claim 1 , wherein the fluorine-containing polymer is composed of agglomerated primary particles having an average particle size of between about 0.2 and about 0.5 μm.

4. The rechargeable battery of claim 1 , wherein the lithium transition metal oxide is selected from the group consisting of:
LiCo d M e O 2 , wherein M comprises one or both of Mg and Ti, with e<0.02 and d+e=1;
Li 1+a M′ 1−a O 2±b M 1 k S m , with −0.03<a<0.06, b<0.02, wherein M′ is a transition metal compound,
wherein at least 95% of M′ are selected from the group consisting of Ni, Mn, Co, Mg and Ti;
M 1 comprises one or more elements selected from the group consisting of Ca, Sr, Y, La, Ce and Zr, with 0≦k≦0.1 in wt %; and 0≦m≦0.6, m being expressed in mol %; and
Li a′ Ni x Co y M″ z O 2±e A f , with 0.9<a′<1.1, 0.5≦x≦0.9, 0<y≦0.4, 0<z≦0.35, e<0.02, 0≦f≦0.05 and 0.9<(x+y+z+f)<1.1; M″ comprises one or more elements selected from the group consisting of Al, Mg, and Ti; and A comprises one or both of S and C.

5. The rechargeable battery of claim 4 , wherein M′=Ni a″ Mn b″ Co c″ , with a″>0, b″>0, c″>0 and a″+b″+c″=1; and a″/b″>1.

6. The rechargeable battery of claim 5 , wherein 0.5≦a″≦0.7, 0.1<c″<0.35, and a″+b″+c″=1.

7. The rechargeable battery of claim 1 , wherein the inner layer comprises a LiF film with a thickness of at least 0.8 nm.

8. The rechargeable battery of claim 7 , wherein the inner layer comprises a LiF film with a thickness of at least 1 nm.

9. A method for manufacturing a rechargeable battery comprising a cathode comprising a primary particle of lithium transition metal oxide powder, the method, comprising:
providing a bare lithium transition metal oxide powder comprising a primary particle,
mixing the primary particle of the bare lithium transition metal oxide powder with a fluorine-containing polymer to form a powder-polymer mixture, and
heating the powder-polymer mixture at a temperature between 50° C. and 140° C. above the melting temperature of the fluorine-containing polymer, whereby, on a surface of the primary particle, a double-layered coating is formed, the coating comprising an inner layer and an outer layer,
the outer layer comprises a partially decomposed fluorine-containing polymer,
the inner layer comprises LiF with a thickness of at least 0.5 nm, and
the surface of the primary particle is Li depleted.

10. The method of claim 9 , wherein the amount of fluorine-containing polymer in the powder-polymer mixture is between 0.1 and 2 wt %.

11. The method of claim 10 , wherein the amount of fluorine-containing polymer in the powder-polymer mixture is between 0.2 and 1 wt %.

12. The method of claim 9 , wherein the inner layer comprises LiF.

13. The method of claim 9 , wherein the fluorine-containing polymer is a PVDF, and the powder-polymer mixture is heated at a temperature between 220 and 325° C. for at least one hour.

14. The method of claim 13 , wherein the fluorine-containing polymer is a PVDF, and the powder-polymer mixture is heated at a temperature between 240 and 275° C.

15. The method of claim 9 , wherein the lithium transition metal oxide is selected from the group consisting of:
LiCo d M e O 2 , wherein M comprises one or both of Mg and Ti, with e<0.02 and d+e=1;
Li 1+a M′ 1−a O 2±b M 1 k S m with −0.03<a<0.06, b<0.02, wherein M′ is a transition metal compound,
wherein at least 95% of M′ comprises one or more elements selected from the group consisting of Ni, Mn, Co, Mg and Ti; M 1 comprises one or more elements selected from the group consisting of Ca, Sr, Y, La, Ce and Zr, with 0≦k≦0.1 in wt %; and 0≦m≦0.6, m being expressed in mol %; and
Li a Ni x Co y M″ z O 2±e A f , with 0.9<a′<1.1, 0.5≦x≦0.9, 0<y≦0.4, 0<z≦0.35, e<0.02, 0≦f≦0.05 and 0.9 (x+y+z+f)<1.1; M″ comprising one or more elements selected from the group consisting of Al, Mg, and Ti; and A comprises one or both of S and C.

16. The method of claim 15 , wherein M′=Ni a″ Mn b″ Co c″ , with a″>0, b″>0, c″>0 and a″+b″+c″=1; and a″/b″>1.

17. The method of claim 16 , wherein 0.5≦a″≦0.7, 0.1<c″<0.35, and a″+b″+c″=1.

18. The method of claim 9 , wherein the inner layer has a thickness of at least 0.8 nm.

19. The method of claim 18 , wherein the inner layer has a thickness of least 1 nm.

Assignees

• Paulsen Jens
• De Palma Randy
• Hong Heonpyo
• Kim Kyubo
• Umicore Nv

Inventors

• Paulsen Jens
• De Palma Randy
• Hong Heonpyo
• Kim Kyubo

Classifications

• H01M4/131

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

• H01M4/1391

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

• H01M4/1315

  containing halogen atoms, e.g. LiCoOxFy · CPC title

• H01M4/366

  as layered products · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic