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

1. A composite electrode active material comprising:

a core, which is capable of intercalating and deintercalating lithium; and

a surface treatment layer disposed on the core,

wherein the surface treatment layer comprises a lithium-free oxide that has a spinel structure and includes a dopant,

wherein the dopant comprises at least one selected from fluorine, sulfur, nitrogen, boron, and phosphorous.

2. The composite electrode active material of claim 1 , wherein the dopant comprises at least one selected from F − , BF 4 − , and PF 6 − .

3. The composite electrode active material of claim 1 , wherein, when analyzed by X-ray photoelectron spectroscopy, as a content of the dopant is increased in the lithium-free oxide, a binding energy of a metal included in the lithium-free oxide is increased.

4. The composite electrode active material of claim 1 , wherein a content ofthe dopant is about 0.1 moles or less, with respect to about 1 mole of the lithium-free oxide.

5. The composite electrode active material of claim 1 , wherein the lithium-free oxide including the dopant is expressed by Chemical Formula 1:

AM 2 O 4−a X a ,  Chemical Formula 1

wherein

0<a≤0.1,

A comprises at least one selected from tin, magnesium, molybdenum, copper, zinc, titanium, nickel, calcium, iron, vanadium, lead, cobalt, germanium, cadmium, mercury, strontium, manganese, aluminum, tungsten, and beryllium,

M comprises at least one selected from magnesium, zinc, aluminum, vanadium, manganese, gallium, chromium, iron, rhodium, nickel, indium, and cobalt,

X comprises at least one selected from fluorine, sulfur, nitrogen, boron, and phosphorous, and

A is different from M.

6. The composite electrode active material of claim 1 , wherein the lithium-free oxide including the dopant comprises at least one selected from SnMg 2 O 4−a X a wherein 0<a≤0.1, SnZn 2 O 4−a X a wherein 0<a≤0.1, MgAl 2 O 4−a X a wherein 0<a≤0.1, MoAl 2 O 4−a X a wherein 0<a≤0.1, CuAl 2 O 4−a X a wherein 0<a≤0.1, ZnAl 2 O 4−a X a wherein 0<a≤0.1, ZnV 2 O 4−a X a wherein 0<a≤0.1, TiMn 2 O 4−a X a wherein 0<a≤0.1, ZnMn 2 O 4−a X a wherein 0<a≤0.1, NiAl 2 O 4−a X a wherein 0<a≤0.1, MgGa 2 O 4−a X a wherein 0<a≤0.1, ZnGa 2 O 4−a X a wherein 0<a≤0.1, CaGa 2 O 4−a X a wherein 0<a≤0.1, TiMg 2 O 4−a X a wherein 0<a≤0.1, VMg 2 O 4−a X a wherein 0<a≤0.1, MgV 2 O 4−a X a wherein 0<a≤0.1, FeV 2 O 4−a X a wherein 0<a≤0.1, ZnV 2 O 4−a X a wherein 0<a≤0.1, MgCr 2 O 4−a X a wherein 0<a≤0.1, MnCr 2 O 4−a X a wherein 0<a≤0.1, FeCr 2 O 4−a X a wherein 0<a≤0.1, CoCr 2 O 4−a X a wherein 0<a≤0.1, NiCr 2 O 4−a X a wherein 0<a≤0.1, CuCr 2 O 4−a X a wherein 0<a≤0.1, ZnCr 2 O 4−a X a wherein 0<a≤0.1, CdCr 2 O 4−a X a wherein 0<a≤0.1, TiMn 2 O 4−a X a wherein 0<a≤0.1, ZnMn 2 O 4−a X a wherein 0<a≤0.1, MgFe 2 O 4−a X a wherein 0<a≤0.1, TiFe 2 O 4−a X a wherein 0<a≤0.1, MnFe 2 O 4−a X a wherein 0<a≤0.1, CoFe 2 O 4−a X a wherein 0<a≤0.1, NiFe 2 O 4−a X a wherein 0<a≤0.1, CuFe 2 O 4−a X a wherein 0<a≤0.1, ZnFe 2 O 4−a X a wherein 0<a≤0.1, CdFe 2 O 4−a X a wherein 0<a≤0.1, AlFe 2 O 4−a X a wherein 0<a≤0.1, PbFe 2 O 4−a X a wherein 0<a≤0.1, MgCo 2 O 4−a X a wherein 0<a≤0.1, TiCo 2 O 4−a X a wherein 0<a≤0.1, ZnCo 2 O 4−a X a wherein 0<a≤0.1, SnCo 2 O 4−a X a wherein 0<a≤0.1, FeNi 2 O 4−a X a wherein 0<a≤0.1, GeNi 2 O 4−a X a wherein 0<a≤0.1, MgRh 2 O 4−a X a wherein 0<a≤0.1, ZnRh 2 O 4−a X a wherein 0<a≤0.1, TiZn 2 O 4−a X a wherein 0<a≤0.1, SrAl 2 O 4−a X a wherein 0<a≤0.1, CrAl 2 O 4−a X a wherein 0<a≤0.1, MoAl 2 O 4−a X a wherein 0<a≤0.1, FeAl 2 O 4−a X a wherein 0<a≤0.1, CoAl 2 O 4−a X a wherein 0<a≤0.1, MgGa 2 O 4−a X a wherein 0<a≤0.1, ZnGa 2 O 4−a X a wherein 0<a≤0.1, MgIn 2 O 4−a X a wherein 0<a≤0.1, CaIn 2 O 4−a X a wherein 0<a≤0.1, FeIn 2 O 4−a X a wherein 0<a≤0.1, CoIn 2 O 4−a X a wherein 0<a≤0.1, NiIn 2 O 4−a X a wherein 0<a≤0.1, CdIn 2 O 4−a X a wherein 0<a≤0.1, and HgIn 2 O 4−a X a wherein 0<a≤0.1, and

wherein X comprises at least one selected from F, S, N, B, and P.

7. The composite electrode active material of claim 1 , wherein the lithium-free oxide including the dopant is expressed by Chemical Formula 1:

AB 2 O 4−a F a ,  Chemical Formula 1

wherein

0<a≤0.1,

A comprises at least one selected from Sn, Mg, Mo, Cu, Zn, Ti, Ni, Ca, Fe, V, Pb, Co, Ge, Cd, Hg, Sr, Mn, Al, W, and Be,

B comprises at least one selected from Mg, Zn, Al, V, Mn, Ga, Cr, Fe, Rh, Ni, In, and Co, and

A is different from B.

8. The composite electrode active material of claim 1 , wherein the lithium-free oxide including the dopant comprises at least one selected from SnMg 2 O 4−a F a wherein 0<a≤0.1, SnZn 2 O 4−a F a wherein 0<a≤0.1, MgAl 2 O 4−a F a wherein 0<a≤0.1, MoAl 2 O 4−a F a wherein 0<a≤0.1, CuAl 2 O 4−a F a wherein 0<a≤0.1, ZnAl 2 O 4−a F a wherein 0<a≤0.1, ZnV 2 O 4−a F a wherein 0<a≤0.1, TiMn 2 O 4−a F a wherein 0<a≤0.1, ZnMn 2 O 4−a F a wherein 0<a≤0.1, NiAl 2 O 4−a F a wherein 0<a≤0.1, MgGa 2 O 4−a F a wherein 0<a≤0.1, ZnGa 2 O 4−a F a wherein 0<a≤0.1, CaGa 2 O 4−a F a wherein 0<a≤0.1, TiMg 2 O 4−a F a wherein 0<a≤0.1, VMg 2 O 4−a F a wherein 0<a≤0.1, MgV 2 O 4−a F a wherein 0<a≤0.1, FeV 2 O 4−a F a wherein 0<a≤0.1, ZnV 2 O 4−a F a wherein 0<a≤0.1, MgCr 2 O 4−a F a wherein 0<a≤0.1, MnCr 2 O 4−a F a wherein 0<a≤0.1, FeCr 2 O 4−a F a wherein 0<a≤0.1, CoCr 2 O 4−a F a wherein 0<a≤0.1, NiCr 2 O 4−a F a wherein 0<a≤0.1, CuCr 2 O 4−a F a wherein 0<a≤0.1, ZnCr 2 O 4−a F a wherein 0<a≤0.1, CdCr 2 O 4−a F a wherein 0<a≤0.1, TiMn 2 O 4−a F a wherein 0<a≤0.1, ZnMn 2 O 4−a F a wherein 0<a≤0.1, MgFe 2 O 4−a F a wherein 0<a≤0.1, TiFe 2 O 4−a F a wherein 0<a≤0.1, MnFe 2 O 4−a F a wherein 0<a≤0.1, CoFe 2 O 4−a F a wherein 0<a≤0.1, NiFe 2 O 4−a F a wherein 0<a≤0.1, CuFe 2 O 4−a F a wherein 0<a≤0.1, ZnFe 2 O 4−a F a wherein 0<a≤0.1, CdFe 2 O 4−a F a wherein 0<a≤0.1, AlFe 2 O 4−a F a wherein 0<a≤0.1, PbFe 2 O 4−a F a wherein 0<a≤0.1, MgCO 2 O 4−a F a wherein 0<a≤0.1, TiCo 2 O 4−a F a wherein 0<a≤0.1, ZnCo 2 O 4−a F a wherein 0<a≤0.1, SnCo 2 O 4−a F a wherein 0<a≤0.1, FeNi 2 O 4−a F a wherein 0<a≤0.1, GeNi 2 O 4−a F a wherein 0<a≤0.1, MgRh 2 O 4−a F a wherein 0<a≤0.1, ZnRh 2 O 4−a F a wherein 0<a≤0.1, TiZn 2 O 4−a F a wherein 0<a≤0.1, SrAl 2 O 4−a F a wherein 0<a≤0.1, CrAl 2 O 4−a F a wherein 0<a≤0.1, MoAl 2 O 4−a F a wherein 0<a≤0.1, FeAl 2 O 4−a F a wherein 0<a≤0.1, CoAl 2 O 4−a F a wherein 0<a≤0.1, MgGa 2 O 4 F a wherein 0<a≤0.1, ZnGa 2 O 4−a F a wherein 0<a≤0.1, MgIn 2 O 4−a F a wherein 0<a≤0.1, CaIn 2 O 4−a F a wherein 0<a≤0.1, FeIn 2 O 4−a F a wherein 0<a≤0.1, CoIn 2 O 4−a F a wherein 0<a≤0.1, NiIn 2 O 4−a F a wherein 0<a≤0.1, CdIn 2 O 4−a F a wherein 0<a≤0.1, and HgIn 2 O 4−a F a wherein 0<a≤0.1.

9. The composite electrode active material of claim 1 , wherein the lithium-free oxide including the dopant comprises at least one selected from SnMg 2 O 4−a F a wherein 0.001≤a≤0.05, SnZn 2 O 4−a F a wherein 0.001≤a≤0.05, MgAl 2 O 4−a F a wherein 0.001≤a≤0.05, CuAl 2 O 4−a F a wherein 0.001≤a≤0.05, ZnAl 2 O 4−a F a wherein 0.001≤a≤0.05, and NiAl 2 O 4−a F a wherein 0.001≤a≤0.05.

10. The composite electrode active material of claim 1 , wherein a content ofthe lithium-free oxide including the dopant is about 50 weight percent or less, with respect to a total weight of the composite electrode active material.

11. The composite electrode active material of claim 1 , wherein the core comprises a negative electrode active material.

12. The composite electrode active material of claim 1 , wherein the core comprises at least one selected from lithium metal, a lithium-alloyable metal, transition metal oxide, and non-transition metal oxide.

13. The composite electrode active material of claim 12 , wherein the core further comprises a carbonaceous material.

14. The composite electrode active material of claim 1 , wherein the core comprises a positive electrode active material.

15. An electrode comprising the composite electrode active material of claim 1 .

16. A lithium battery comprising the electrode of claim 15 .

17. A method of preparing a composite electrode active material, the method comprising:

providing a lithium-free oxide that has a spinel structure and includes a dopant;

mixing a core comprising an electrode active material and the lithium-free oxide including the dopant together to form a mixture; and

milling the mixture using a dry method to form, on the core, a surface treatment layer comprising the lithium-free oxide that includes the dopant to prepare the composite electrode active material,

wherein the dopant comprises at least one selected from fluorine, sulfur, nitrogen, boron, and phosphorous.

18. The method of claim 17 , wherein the dry method comprises at least one selected from a planetary ball mill method, a ball mill method, a hybridization method, and a mechanofusion method.

19. The method of claim 17 , wherein the providing of the lithium-free oxide including the dopant comprises:

milling a lithium-free oxide and a dopant precursor to prepare a mixture; and

sintering the mixture to prepare the lithium-free oxide including the dopant.

20. The method of claim 17 , wherein the preparing of the lithium-free oxide including the dopant comprises:

milling a lithium-free oxide precursor and a dopant precursor to prepare a mixture; and

oxidizing the mixture to prepare the lithium-free oxide including the dopant.