Lithium ion manganese oxide battery

A Lithium ion manganese oxide battery is a lithium ion cell that uses manganese dioxide, MnO
2, as the primary cathode material. They function through the same intercalation/de-intercalation mechanism as other commercialized secondary battery technologies, such as LiCoO
2. They are a promising technology as their manganese-oxide components are earth-abundant, inexpensive, non-toxic, and provide better thermal stability.[1]

Compounds

Spinel LiMn
2O
4

One of the more prominent compounds is LiMn
2O
4, a lithium-manganese-oxide based material with a spinel structure (space group Fd3m). In addition to being a cheap and non-toxic alternative material, the spinel structure of LiMn
2O
4 provides a three-dimensional framework for the insertion and de-insertion of Li+
 ions during discharge and charge of the battery. In particular, the Li+
 ions occupy the interstitial spaces defined by the Mn
2O
4 polyhedral frameworks.[2] Thus, batteries with LiMn
2O
4 cathodes should be able to provide a higher rate-capability compared to materials with two-dimensional frameworks for Li+
 diffusion.[3]

One main disadvantage of LiMn
2O
4 based batteries is that they suffer from lower overall capacities as a result of their spinel structure. Furthermore, at higher temperatures, the LiMn
2O
4 spinel structure is inherently unstable in the Li-based electrolytes used in Li-ion batteries. This results in dissolution of Mn ions and further capacity loss.[4]

Layered Li
2MnO
3

Li
2MnO
3 is layered rocksalt structure that is made of alternating layers of lithium ions and lithium and manganese ions in a 1:2 ratio, similar to the layered structure of LiCoO
2.[5] Although Li
2MnO
3 is electrochemically inactive and, it can be charged to a high potential (4.5 V v.s Li0) in order to undergo lithiation/de-lithiation.[6] However, extracting lithium from Li
2MnO
3 at such a high porential results in loss of oxygen from the electrode surface which leads to poor capacity and cycling stability.[7]

Research

One of the main research efforts in the field of lithium-manganese oxide electrodes for lithium-ion batteries involves developing composite electrodes using structurally integrated layered Li
2MnO
3 and spinel LiMn
2O
4, with a chemical formula of xLi
2MnO
3 • (1-x)Li
1+yMn
2-yO
4. The combination of both structures provides increased structural stability during electrochemical cycling while achieving higher capacity and rate-capability. A rechargeable capacity in excess of 250 mAh/g was reported in 2005 using this material, which has nearly twice the capacity of current commercialized rechargeable batteries of the same dimensions.[8]

See also

References

  1. ↑ Thackeray, Michael M. "Manganese oxides for lithium batteries." Progress in Solid State Chemistry 25.1 (1997): 1-71.
  2. ↑ Thackeray, M. M., et al. "Electrochemical extraction of lithium from LiMn 2 O 4." Materials Research Bulletin 19.2 (1984): 179-187.
  3. ↑ M. Lanz, C. Kormann, H. Steininger, G. Heil, O. Haas, P.Novak, J. Electrochem. Soc. 147 (2000) 3997.
  4. ↑ A. Du Pasquier, A. Blyr, P. Courjal, D. Larcher, G. Amatucci,B. Gerand, J.M. Tarascon, J. Electrochem. Soc. 146 (1999) 428
  5. ↑ Thackeray, Michael M., et al. "Advances in manganese-oxide ‘composite’electrodes for lithium-ion batteries." Journal of Materials Chemistry 15.23 (2005): 2257-2267.
  6. ↑ P. Kalyani, S. Chitra, T. Mohan and S. Gopukumar, J. Power Sources, 1999, 80, 103.
  7. ↑ A. Robertson and P. G. Bruce, Chem. Mater., 2003, 15, 1984.
  8. ↑ Johnson, C. S., et al. "Lithium–manganese oxide electrodes with layered–spinel composite structures x Li
    2    MnO
    3    ·(1− x) Li
    1+ y    Mn
    2− y    O
    4     (0< x< 1, 0⩽ y⩽ 0.33) for lithium batteries." Electrochemistry communications 7.5 (2005): 528-536.
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