Lithium-oxygen (AIR) electrochemical cells and batteries

1. A lithium-oxygen or lithium-air electrochemical cell comprising a negative electrode, an electrolyte, and a porous activated positive electrode produced by activating a precursor positive electrode formed from a material comprising one or more metal oxide compounds having the general formula xLi 2 O.yMO z , in which 0≦x4, 0≦y≦1, and 0<z≦3, in which M is a metal ion, excluding Li 2 MnO 3 as a sole metal oxide compound in the precursor electrode, wherein the electrode is activated by removing Li 2 O from at least one metal oxide compound of the precursor electrode, wherein the positive electrode is supplied with oxygen during discharge of the cell.

2. The electrochemical cell of claim 1 , wherein the precursor electrode material is crystalline, partially crystalline, or amorphous.

3. The electrochemical cell of claim 1 , wherein the precursor electrode material has a cation-deficient or anion-deficient structure.

4. The electrochemical cell of claim 1 , wherein the precursor electrode material comprises anion- or cation-substituted compositions and structures.

5. The electrochemical cell of claim 1 , wherein M comprises one or more metals selected from the group consisting of 1st, 2nd and 3rd row transition metals.

6. The electrochemical cell of claim 5 , wherein M comprises a metal selected from the group consisting of V, Mn, Fe, Ni, Co, Mo, Ru, Pt and Ir.

7. The electrochemical cell of claim 5 , wherein M is partially substituted by Li.

8. The electrochemical cell of claim 5 , wherein oxygen ions of the compound of general formula xLi 2 O.yMO z are partially substituted by fluorine ions.

9. The electrochemical cell of claim 5 , wherein M is partially substituted by one or more_non-transition metal ions.

10. The electrochemical cell of claim 9 , wherein the non-transition metal ions are selected from the group consisting of Mg 2+ , Al 3+ and Si + and P 5+ ions.

11. The electrochemical cell of claim 1 , wherein precursor electrode comprises one or more of LiV 3 O 8 (Li 2 O.3V 2 O 5 ), Li 3 VO 4 (3Li 2 O.V 2 O 5 ), Li 4 Mn 5 O 12 (2Li 2 O.5MnO 2 ), Li 0.3 MnO 2.15 (0.15Li 2 O.MnO 2 ), LiFeO 2 (Li 2 O.Fe 2 O 3 ), Li 2 MoO 4 (4Li 2 O.MoO 3 ) Li 2 RuO 3 (Li 2 O.RuO 2 ), Li 8 PtO 6 (4Li 2 O.PtO 2 ) and Li 8 IrO 6 (4Li 2 O.IrO 2 ), or Li 2 MnO 3 in combination with one or more of the foregoing compounds.

12. The electrochemical cell of claim 1 , wherein the precursor electrode material has an antifluorite-type structure or a defect antifluorite-type structure.

13. The electrochemical cell of claim 12 , wherein the precursor electrode comprises one or more materials selected from the group consisting of Li 5 FeO 4 (5Li 2 O.Fe 2 O 3 ), Li 6 CoO 4 (3Li 2 O.CoO), Li 6 NiO 4 (3Li 2 O.NiO), and Li 6 MnO 4 (3Li 2 O.MnO), or Li 2 MnO 3 in combination with one or more of the foregoing compounds.

14. The electrochemical cell of claim 1 , wherein the precursor electrode further comprises one or more of a metal catalyst, a catalytic compound, or a combination thereof.

15. The electrochemical cell of claim 14 , wherein the metal catalyst comprises one or more transition-metal or precious-metal elements.

16. The electrochemical cell of claim 14 , wherein the metal catalyst comprises one or more of Fe, Mn, Co, Ni, Ru, Pt, and Ir.

17. The electrochemical cell of claim 14 , wherein the catalytic compound comprises a metal oxide.

18. The electrochemical cell of claim 17 , wherein the metal oxide is MnO 2 or V 2 O 5 .

19. The electrochemical cell of claim 1 , wherein the precursor electrode comprises primary and secondary particles with an average primary particle less than 1 micron and an average secondary particle less than 50 microns.

20. The electrochemical cell of claim 19 , wherein the primary particles have an average size of 500 nm or less.

21. The electrochemical cell of claim 19 , wherein the primary particles have an average size of 200 nm or less.

22. The electrochemical cell of claim 19 , wherein the primary particles have an average size of 100 nm or less.

23. The electrochemical cell of claim 1 , wherein the electrode is activated by applying a sufficiently high potential to the precursor electrode to remove Li 2 O from the positive electrode.

24. The electrochemical cell of claim 23 , wherein the lithium from the Li 2 O removed from the positive electrode is loaded into the negative electrode of the cell.

25. The electrochemical cell of claim 1 , wherein the positive electrode is activated by acid treatment to remove Li 2 O from the precursor electrode material or to effect H + ion exchange for the lithium ions, or both.

26. The electrochemical cell of claim 1 , wherein the positive electrode is activated by removing Li 2 O from the positive electrode during a charging process.

27. The electrochemical cell of claim 1 , wherein the oxygen supplied to the positive electrode comprises pure oxygen, air, or oxygen diluted with an electrochemically inert gas.

28. The electrochemical cell of claim 1 , wherein the negative electrode of the electrochemical cell comprises one or more of a carbon material, a metal material, a semi-metal material, an intermetallic material, and a metal oxide material.

29. The electrochemical cell of claim 1 , wherein the negative electrode of the electrochemical cell comprises one or more of amorphous carbon, graphite, Li, Sn, Si, Cu 6 Sn 5 , and Li 4 Ti 5 O 12 .

30. The electrochemical cell of claim 1 , wherein the electrolyte of the electrochemical cell comprises one or more of a solid electrolyte and a liquid electrolyte.

31. The electrochemical cell of claim 1 , wherein the electrolyte of the electrochemical cell comprises one or more of a solid electrolyte and a non-aqueous liquid electrolyte.

32. A lithium battery comprising a plurality of electrically connected electrochemical lithium-oxygen or lithium-air cells of claim 1 .