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Electrical Conductivity and Electrochemical Characteristics of Na3V2(PO4)3-Based NASICON-Type Materials

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Inorganic Materials Aims and scope

Abstract

NASICON-type materials with the compositions Na3V2–xAlx(PO4)3, Na3V2 - xFex(PO4)3, Na3 + xV2–xNix(PO4)3, and Na3V2 - xCrx(PO4)3 (x = 0, 0.03, 0.05, and 0.1) have been prepared and characterized by X-ray diffraction analysis, electron microscopy, and impedance spectroscopy. The results demonstrate that the highest electrical conductivity among the samples studied is offered by the material doped with 5% Fe: Na3V1.9Fe0.1(PO4)3. The activation energy for low-temperature conduction in the doped materials decreases from 84 ± 2 to 54 ± 1 kJ/mol and that for high-temperature conduction is ~33 kJ/mol. The discharge capacity of Na3V1.9Fe0.1(PO4)3/C under typical working conditions of cathodes of sodium ion batteries has been shown to exceed that of Na3V2(PO4)3/C. The capacity of the more porous material prepared by the Pechini process (Na3V1.9Fe0.1(PO4)3/C-{II}) approaches the theoretical one at a low charge–discharge rate and retains its high level as the charge rate is raised (its discharge capacity was 117.6, 108.8, and 82.6 mAh/g at a discharge rate of 0.1C, 2C, and 8C, respectively).

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Authors and Affiliations

  1. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow, 119991, Russia

    S. A. Novikova & A. B. Yaroslavtsev

  2. Faculty of Chemistry, Moscow State University, Moscow, 119991, Russia

    R. V. Larkovich

  3. Skolkovo Institute of Science and Technology, ul. Nobelya 3, Moscow, 143026, Russia

    A. A. Chekannikov

  4. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninskii pr. 31/4, Moscow, 119071, Russia

    T. L. Kulova & A. M. Skundin

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Original Russian Text © S.A. Novikova, R.V. Larkovich, A.A. Chekannikov, T.L. Kulova, A.M. Skundin, A.B. Yaroslavtsev, 2018, published in Neorganicheskie Materialy, 2018, Vol. 54, No. 8.

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Novikova, S.A., Larkovich, R.V., Chekannikov, A.A. et al. Electrical Conductivity and Electrochemical Characteristics of Na3V2(PO4)3-Based NASICON-Type Materials. Inorg Mater 54, 794–804 (2018). https://doi.org/10.1134/S0020168518080149

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