Rechargeable aluminum ion battery

1. An aluminum-ion secondary battery comprising:

an anode comprising aluminum, an aluminum alloy, or an aluminum compound;

a cathode comprising a bulk cathode material having sufficient porosity and inter-sheet voids to accommodate reversible insertion of polyatomic ions comprising aluminum into the bulk material;

a porous separator comprising an electrically insulating material that prevents direct contact of the anode and the cathode; and

an electrolyte that is an aqueous solution comprising an aluminum salt, wherein electrolyte is in contact with the anode and with the cathode,

wherein the battery is operable to charge and discharge by causing transport of the polyatomic ions comprising aluminum between the cathode and the anode and the battery is environmentally sealed.

2. The secondary battery of claim 1 , wherein the material is a manganese oxide.

3. The secondary battery of claim 2 , wherein the manganese oxide is a lithium manganese oxide that has been subjected to an acid treatment.

4. The secondary battery of claim 2 , wherein the manganese oxide is manganese dioxide.

5. The secondary battery of claim 1 , wherein the aluminum in the polyatomic ions has a valence of 3+ and the polyatomic ions have a valence of lower magnitude.

6. The secondary battery of claim 5 , wherein the valence of lower magnitude is 1—.

7. The secondary battery of claim 1 , wherein the polyatomic ions are Al(OH) 4 1− .

8. The secondary battery of claim 1 , wherein a concentration of the aluminum salt in the aqueous solution is in a range from 0.05 M to 5 M.

9. The secondary battery of claim 8 , wherein the concentration of the aluminum salt in the aqueous solution is in a range from about 0.5 M to about 3 M.

10. The secondary battery of claim 1 , wherein the aluminum salt is aluminum nitrate.

11. The secondary battery of claim 10 , wherein a concentration of the aluminum nitrate in the aqueous solution is in a range from 0.05 M to 5 M.

12. The secondary battery of claim 11 , wherein the concentration of the aluminum nitrate in the aqueous solution is in a range from about 0.5 M to about 3 M.

13. The secondary battery of claim 1 , wherein the material is a manganese oxide and the salt is aluminum nitrate.

14. The secondary battery of claim 13 , wherein the manganese oxide is manganese dioxide.

15. The secondary battery of claim 1 , wherein the aluminum salt is selected from the group consisting of aluminum sulfate, aluminum phosphate, aluminum bromide hexahydrate, aluminum fluoride, aluminum fluoride trihydrate, aluminum iodide hexahydrate, aluminum perchlorate, aluminum hydroxide, and combinations thereof.

16. The secondary battery of claim 1 , wherein the cathode comprises a material selected from the group consisting of a lithium manganese oxide, an acid-treated lithium manganese oxide, a lithium metal manganese oxide (where the metal is selected from the group consisting of nickel, cobalt, aluminum, chromium and combinations thereof), and an acid-treated lithium metal manganese oxide.

17. The secondary battery of claim 1 , wherein the anode comprises the aluminum alloy and the aluminum alloy comprises aluminum and at least one element selected from the group consisting of manganese, magnesium, lithium, zirconia, iron, cobalt, tungsten, vanadium, nickel, copper, silicon, chromium, titanium, tin, and zinc.

18. The secondary battery of claim 1 , wherein the anode is the aluminum and the aluminum has received a treatment that is effective to increase the hydrophilic properties of a surface of the anode that is in contact with the electrolyte, wherein the treatment comprises contacting the surface of the aluminum with an aqueous solution of a member selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, and mixtures thereof.

19. The secondary battery of claim 1 , wherein the anode comprises the aluminum compound and the aluminum compound is selected from the group consisting of an aluminum transition metal oxide (Al x M y O z , where M is a transition metal selected from the group consisting of iron, vanadium, titanium, molybdenum, copper, nickel, zinc, tungsten, manganese, chromium, cobalt and mixtures thereof and x, y, and z range from 0 to 8, inclusive); an aluminum transition metal sulfide, (Al x M y S z , where M is a transition metal selected from the group consisting of iron, vanadium, titanium, molybdenum, copper, nickel, zinc, tungsten, manganese, chromium, cobalt and mixtures thereof and x, y, and z range from 0 to 8, inclusive); aluminum lithium cobalt oxide (AlLi 3 CoO 2 ); lithium aluminum hydride (LiAlH 4 ); sodium aluminum hydride (NaAlH 4 ); potassium aluminum fluoride (KAlF 4 ); and mixtures thereof.

20. The secondary battery of claim 1 , wherein the electrolyte further comprises an alkali metal hydroxide selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonium hydroxide, calcium hydroxide, magnesium hydroxide, and mixtures thereof.

21. The secondary battery of claim 1 , wherein the electrolyte further comprises an aluminum halide selected from the group consisting of aluminum chloride, aluminum bromide, aluminum iodide, and mixtures thereof.

22. The secondary battery of claim 1 , wherein the porous separator has an average pore size of 0.067 μm to 1.2 μm.

23. The secondary battery of claim 1 , wherein the aluminum salt is aluminum sulfate.

24. The secondary battery of claim 1 , wherein the aluminum salt is aluminum phosphate.

25. The secondary battery of claim 1 , wherein the electrolyte comprises sodium nitrate.

26. The secondary battery of claim 1 , wherein the material is a manganese oxide structured to accommodate reversible insertion of the polyatomic ions comprising aluminum into the manganese oxide.

27. The secondary battery of claim 1 , wherein the battery is environmentally sealed in a coin cell, a prismatic cell, or a pouch cell.