Manganese oxide based materials as ion intercalation hosts in lithium batteries

• US 20050135993A1
• Filed: 12/23/2003
• Published: 06/23/2005
• Est. Priority Date: 12/23/2003
• Status: Abandoned Application

• Current Assignee: Rutgers University
• Original Assignee: Rutgers University
• Inventors: Jain, Gaurav, Xu, Jun, Yang, Jingsi
• Application Number:
  US10/744,395
• Publication Number:
  US 20050135993A1
• Time in Patent Office: Days
• US Class Current: 423/605
• CPC Class Codes: C01G 45/02 Oxides; Hydroxides
• CPC Class Codes: C01G 45/1221 Manganates or manganites with a manganese oxidation state of Mn(III), Mn(IV) or mixtures thereof
• CPC Class Codes: C01G 45/1228 of the type [MnO2]n- , e.g. LiMnO2, Li[MxMn1-x]O2
• CPC Class Codes: C01G 45/125 of the type[MnO3]n-, e.g. Li2MnO3, Li2[MxMn1-xO3], (La,Sr)MnO3
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2006/12 Surface area
• CPC Class Codes: C01P 2006/40 Electric properties
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention is directed to a process for making an amorphous nanostructured cation-doped manganese oxide material useful as an ion intercalation host for rechargeable batteries, including the steps of preparing a solution containing cation permanganate combined optionally with a cation donor compound, mixing the solution with a reducing agent to yield a hydrogel comprising a manganese oxide compound, cryogenically freezing the hydrogel, drying the frozen gel to yield a cryogel amorphous nanostructured cation-doped manganese oxide, and heat treating the dried cryogel.

Claims

1. An amorphous nanostructured material useful as an ion intercalation host for rechargeable batteries, comprising a cryogel derived from a freeze dried hydrogel, wherein the hydrogel is formed from a sol-gel reaction.

2. The amorphous nanostructured material of claim 1, is a manganese oxide compound.

3. The amorphous nanostructured material of claim 2, wherein the manganese oxide compound comprises the formula R_xMnO_2+y/2, wherein R is a doped cation, and x and y are selected from 0 to 2.

4. The amorphous nanostructured material of claim 3, wherein the doped cation is selected from the group consisting of lithium, sodium, copper, and combinations thereof.

5. The amorphous nanostructured material of claim 1, wherein the cryogel exhibits a specific capacity of at least 80 mAh/g.

6. The amorphous nanostructured material of claim 5, wherein the cryogel exhibits a specific capacity of from about 80 to 250 mAh/g.

7. The amorphous nanostructured material of claim 1, wherein the cryogel exhibits a Brauner-Emmet-Teller (BET) surface area of at least 300 m²/g.

8. The amorphous nanostructured material of claim 1, wherein the sol-gel reaction comprises a reaction between a permanganate salt and a reducing agent.

9. The amorphous nanostructured material of claim 8, wherein the permanganate salt is selected from the group consisting of lithium permanganate and sodium permanganate.

10. The amorphous nanostructured material of claim 8, wherein the reducing agent is selected from the group consisting of fumaric acid and disodium fumarate.

11. A process for making an amorphous nanostructured material useful as an ion intercalation host for rechargeable batteries, comprising the steps of:

preparing an oxide in the form of a hydrogel;

cryogenically freezing the hydrogel; and

drying the frozen gel to yield an amorphous nanostructured oxide cryogel material.

12. The process of claim 11, wherein the oxide is a manganese oxide compound.

13. The process of claim 12, wherein the manganese oxide compound comprises the formula R_xMnO_2+y/2, wherein R is a doped cation, and x and y are selected from 0 to 2.

14. The process of claim 13, wherein the doped cation is selected from the group consisting of lithium, sodium, copper, and combinations thereof.

15. The process of claim 11, wherein the cryogel exhibits a specific capacity of at least 80 mAh/g.

16. The process of claim 11, wherein the cryogel exhibits a specific capacity of from about 80 to 250 mAh/g.

17. The process of claim 11, wherein the cryogel exhibits a Brauner-Emmet-Teller (BET) surface area of at least 300 m²/g.

18. The process of claim 11, wherein the preparing step comprises reacting a permanganate salt with a reducing agent.

19. The process of claim 18, wherein the permanganate salt is selected from the group consisting of lithium permanganate and sodium permanganate.

20. The process of claim 18, wherein the reducing agent is selected from the group consisting of fumaric acid and disodium fumarate.

21. The process of claim 11, wherein the preparing step comprises:

preparing a solution containing a permanganate salt combined optionally with a cation donor compound; and

mixing the solution with a reducing agent to yield the hydrogel comprising a manganese oxide.

22. The process of claim 21, further comprising the step of heat treating the dried cryogel.

23. The process of claim 22, wherein the heat treating step further comprises heating the dried cryogel at a temperature and for a time sufficient to induce the manganese to exhibit an oxidation state of 4+.

24. The process of claim 23, wherein the temperature is less than 400°

C.

25. The process of claim 23, wherein the temperature is from about 250°

C. to 400°

C.

26. The process of claim 23, wherein the time is at least 1 hour.

27. The process of claim 23, wherein the time is at least 12 hours.

28. The process of claim 11, wherein the cryogenically freezing step comprises treating the hydrogel with a cryogenic liquid.

29. The process of claim 28, wherein the cryogenic liquid is liquid nitrogen.

30. The process of claim 11, wherein the drying step comprises vacuum drying the cryogel.

31. The process of claim 11, wherein the heat treating step comprises heating the dried cryogel at a temperature of less than 400°

C. for at least 1 hour.

53. An amorphous nanostructured oxide material useful as an ion intercalation host for rechargeable batteries, prepared by the process of claim 11.

32. A process for making an amorphous nanostructured cation-doped manganese oxide material useful as an ion intercalation host for rechargeable batteries, comprising the steps of:

preparing a solution comprising a cation containing permanganate salt combined optionally with a cation donor compound;

mixing the solution with a reducing agent to yield a hydrogel comprising a manganese oxide material;

cryogenically freezing the hydrogel; and

drying the frozen gel to yield an amorphous nanostructured cation-doped manganese oxide cryogel material.

33. The process of claim 32, further comprising the step of heat treating the dried cryogel.

34. The process of claim 33, wherein the heat treating step further comprises heating the dried cryogel at a temperature and for a time sufficient to induce the manganese to exhibit an oxidation state of 4+.

35. The process of claim 34, wherein the temperature is less than 400°

C.

36. The process of claim 34, wherein the temperature is from about 250°

C. to 400°

C.

37. The process of claim 34, wherein the time is at least 1 hour.

38. The process of claim 34, wherein the time is at least 12 hours.

39. The process of claim 32, wherein the cryogenically freezing step comprises treating the hydrogel with a cryogenic liquid.

40. The process of claim 39, wherein the cryogenic liquid is liquid nitrogen.

41. The process of claim 32, wherein the drying step comprises vacuum drying the cryogel.

42. The process of claim 32, wherein the heat treating step comprises heating the dried cryogel at a temperature of less than 400°

C. for at least 1 hour.

43. The process of claim 32, wherein the cation is selected from the group consisting of lithium, sodium, and copper.

44. The process of claim 32, wherein the reducing agent is selected from the group consisting of fumaric acid, and disodium fumarate.

45. The process of claim 32, wherein the manganese oxide material comprises the formula RxMnO_2+y/2, wherein R is a doped cation, and x and y range from 0 to 2.

46. The process of claim 45, wherein the doped cation is selected from the group consisting of lithium, sodium, copper, and combinations thereof.

47. The process of claim 32, wherein the cryogel exhibits a specific capacity of at least 80 mAh/g.

48. The process of claim 32, wherein the cryogel exhibits a specific capacity of from about 80 to 250 mAh/g.

49. The process of claim 32, wherein the cryogel exhibits a Brauner-Emmet-Teller (BET) surface area of at least 300 m²/g.

50. The process of claim 32, wherein the permanganate salt is selected from the group consisting of lithium permanganate and sodium permanganate.

51. The process of claim 32, wherein the reducing agent is selected from the group consisting of fumaric acid and disodium fumarate.

52. A process for making an amorphous nanostructured lithium-containing manganese oxide material useful as an ion intercalation host for rechargeable batteries, comprising the steps of:

preparing a solution containing lithium permanganate combined optionally with lithium hydroxide;

mixing the solution with a reducing agent to yield a hydrogel;

freezing the hydrogel in a liquefied gas;

drying the frozen gel to yield an amorphous nanostructured lithium-containing manganese oxide cryogel; and

optionally, heat treating the dried cryogel.