Lithium titanate and lithium cells and batteries including the same
View Patent ↗An active material suitable for use in lithium cells comprises lithium titanate having a surface and a material disposed on the surface is provided. The material is non-reactive with an electrolyte within a range of potential vs. lithium of from 0 V to 4 V. A variety of lithium cells including lithium titanate are also provided. The lithium titanate is typically of the general formula: Li 4 Ti 5 O 12-x , wherein x is greater than 0. Further, a cell module is provided. The cell module comprises a plurality of lithium cells each having a soft outer packaging and assembled in an environment where water content in the environment is controlled.
1. An active material suitable for use in lithium cells, said active material comprising:
lithium titanate having a surface; and
a material selected from the group consisting of polyethylene oxide, polymethylene-polyethylene oxide, polyphosphaznes and combinations thereof disposed on said surface of said lithium titanate, said material being non-reactive with an electrolyte within a range of potential vs. lithium of from 0 V to 4 V while said active material is in the presence of the electrolyte.
2. An active material as set forth in claim 1 wherein said material does not decompose the electrolyte.
3. An active material as set forth in claim 1 wherein said lithium titanate has the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
4. An active material as set forth in claim 3 wherein x is less than 0.02.
5. An active material as set forth in claim 4 wherein an average valence of titanium in said lithium titanate is less than 4.
6. A lithium cell comprising said active material as set forth in claim 1 .
7. A lithium cell as set forth in claim 6 further comprising an electrolyte.
8. A lithium cell comprising at least two electrodes each comprising lithium titanate, said lithium cell having an electrode potential versus lithium in a general condition of use that does not drop below 1.3 V.
9. A lithium cell as set forth in claim 8 wherein said lithium titanate has the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
10. A lithium cell as set forth in claim 9 wherein x is less than 0.02.
11. A lithium cell as set forth in claim 10 wherein an average valence of titanium in said lithium titanate is less than 4.
12. A lithium cell comprising:
lithium titanate;
lithium bis(oxalate)borate; and
a surface film disposed on said lithium titanate and formed by said electrolyte.
13. A lithium cell as set forth in claim 12 wherein said lithium titanate has the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
14. A lithium cell as set forth in claim 13 wherein x is less than 0.02.
15. A lithium cell as set forth in claim 14 wherein an average valence of titanium in said lithium titanate is less than 4.
16. A lithium cell comprising:
at least one electrode comprising lithium titanate; and
a non-fluorinated binder, wherein said lithium titanate has the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
17. A lithium cell as set forth in claim 16 wherein x is less than 0.02.
18. A lithium cell as set forth in claim 17 wherein an average valence of titanium in said lithium titanate is less than 4.
19. A lithium cell comprising at least one electrode, said electrode comprising:
a first lithium titanate having the following formula:
Li 4 Ti 5 O 12-x
and
a second lithium titanate different from said first lithium titanate, said second lithium titanate having the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12;
said second lithium titanate being present in said electrode in an amount greater than that of said first lithium titanate.
20. A lithium cell as set forth 19 wherein said electrode includes at least 10% more of said second lithium titanate relative to said first lithium titanate.
21. A lithium cell as set forth in claim 20 wherein x is less than 0.02.
22. A lithium cell as set forth in claim 21 wherein an average valence of titanium in said lithium titanate is less than 4.
23. A lithium cell comprising:
an anode and cathode wherein said cathode comprises a lithium titanate and a gas absorbing material and
a gas absorbing material, wherein said lithium titanate and said gas absorbing material are mixed to form an electrode.
24. A lithium cell as set forth in claim 23 wherein said the gas absorbing material is selected from the group of ZnO, NaAlO 2 , silicon, and combinations thereof.
25. A lithium cell as set forth in claim 23 further comprising a separator and wherein gas absorbing material is retained by said separator.
26. A lithium cell as set forth in claim 23 further comprising a case and wherein said gas absorbing material is retained by said case.
27. A lithium cell as set forth in claim 23 wherein said lithium titanate has the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
28. A lithium cell as set forth in claim 27 wherein x is less than 0.02.
29. A lithium cell as set forth in claim 28 wherein an average valence of titanium in said lithium titanate is less than 4.
30. A lithium cell as set forth in claim 28 wherein said the gas absorbing material is selected from the group of ZnO, NaAlO 2 , silicon, and combinations thereof.
31. A lithium cell comprising:
an electrode comprising a lithium titanate having the following formula:
Li 4 Ti 5 O 12-x
wherein x is greater than 0 and less than 12.
32. A lithium cell as set forth in claim 31 wherein x is less than 0.02.