Cobalt-free layered oxide cathodes

1. A cathode comprising a lithium metal oxide, the lithium metal oxide comprising nickel, aluminum, and iron, wherein the lithium metal oxide is substantially free of cobalt, wherein the cathode comprises a primary particle having a surface with the primary particle comprising the lithium metal oxide, and wherein the primary particle comprises an oxide coating disposed on the surface.

2. The cathode of claim 1 , wherein the lithium metal oxide the lithium metal oxide has a formula according to Formula I:

Li 1+w Ni x Fe y Al z O 2   I;

wherein 0≤w≤0.05, 0<x<1, 0<y≤0.2, 0<z≤0.2, and x+y+z=1.

3. The cathode of claim 2 , wherein the lithium metal oxide has a formula according to Formula II:

LiNi 0.8 Fe 0.1 Al 0.1 O 2   II.

4. The cathode of claim 1 , wherein the iron of the lithium metal oxide is selected from the group of Fe 2+ , Fe 3+ , and combinations thereof.

5. The cathode of claim 4 , wherein the iron of the lithium metal oxide comprises Fe 3+ .

6. The cathode of claim 1 , wherein the aluminum of the lithium metal oxide comprises Al 3+ .

7. The cathode of claim 1 , wherein the cathode comprising iron and substantially free of cobalt exhibits an increase in capacity as compared to a conventional cathode free of iron and comprising cobalt.

8. The cathode of claim 1 , wherein the primary particle has a spherical configuration or a hexagonal-shaped nano-plate configuration.

9. The cathode of claim 1 , wherein the oxide coating comprises an oxide selected from the group of silicon dioxide, zirconium dioxide, titanium oxide, and a combination thereof.

10. A cathode comprising a lithium metal oxide, the lithium metal oxide comprising nickel, aluminum, and iron, wherein the lithium metal oxide is substantially free of cobalt,

wherein the cathode comprises a primary particle having a surface with the primary particle comprising the lithium metal oxide,

wherein the primary particle has a hexagonal-shaped nano-plate configuration, and wherein the cathode may exhibit improved lithium ion diffusion through the primary particle having the hexagonal-shaped nano-plate configuration relative to a primary particle that does not have the hexagonal-shaped plate configuration.

11. A battery comprising: an anode; a cathode comprising a lithium metal oxide, the lithium metal oxide comprising nickel, aluminum, and iron, wherein the lithium metal oxide is substantially free of cobalt, wherein the cathode comprises a primary particle having a surface with the primary particle comprising the lithium metal oxide, and the primary particle comprises an oxide coating disposed on the surface; and an electrolyte.

12. The battery of claim 11 , wherein the lithium metal oxide has a formula according to Formula I:

Li 1+w Ni x Fe y Al z O 2   I;

wherein 0≤w≤0.05, 0<x<1, 0<y≤0.2, 0<z≤0.2, and x+y+z=1.

13. The battery of claim 12 , wherein the lithium metal oxide has a formula according to Formula II:

LiNi 0.8 Fe 0.1 Al 0.1 O 2   II.

14. The battery of claim 11 , wherein the anode comprises a lithium titanium oxide.

15. The battery of claim 14 , wherein the lithium titanium oxide has a formula according to Formula III:

Li 4 Ti 5 O 12   III.

16. The battery of claim 11 , wherein the electrolyte comprises a mixture of LiPF 6 , ethylene carbonate, and ethyl methyl carbonate.

17. The battery of claim 16 , wherein the mixture further comprises an electrolyte additive selected from the group of fluorinated carbonates, anhydrides, sulfones, sulfites, and combinations thereof.

18. A method of forming the lithium metal oxide of claim 1 , the method comprising:

dissolving lithium, nickel, aluminum, and iron in an aqueous solvent to form a solution;

heating the solution to a first temperature to form a gel;

evaporating the aqueous solvent from the gel to form a precursor powder; and

heating the precursor powder to a second temperature, different than the first temperature, for calcinating the precursor powder to form the lithium metal oxide.