Journal of Materials Science

, Volume 54, Issue 9, pp 7131–7155 | Cite as

Dielectric relaxations and transport properties parameter analysis of novel blended solid polymer electrolyte for sodium-ion rechargeable batteries

  • Pritam
  • Anil Arya
  • A. L. SharmaEmail author
Energy materials


A novel blended solid polymer electrolyte comprising polyethylene oxide and polyvinylpyrrolidone polymers for blending and sodium nitrate (NaNO3) as ion conducting species has been optimized via standard solution-cast technique. XRD, FESEM, and FTIR were performed to obtain the information about the structural changes, morphology, and microstructural changes (polymer–ion and ion–ion interactions) of the solid polymer electrolyte films. The electrochemical impedance spectroscopy, linear sweep voltammetry, and it characteristics were performed to evaluate the ionic conductivity, voltage stability window, and ion transference number. The impedance study was done in a broad temperature range (40–100 °C). The DSC and TGA were used to obtain information about the thermal transitions and thermal stability of prepared films. The ion dynamics is further investigated by analyzing the complex permittivity, loss tangent, and complex conductivity. All the plots were fitted through established theoretical model/expressions in whole frequency window to obtain dielectric strength, ion conduction path behavior, and relaxation time. Transport parameters such as number density (n), mobility (μ), and diffusion coefficient (D) of mobile ions were obtained by three methods and compared satisfactorily. Lastly, a coherent mechanism for the migration of charge transport carriers within the solid polymer composites has been proposed based on the performed experimental outcome.



One of the authors (Pritam) is thankful to CSIR, New Delhi for the award of JRF fellowship. AA is thankful to the Central University of Punjab, Bathinda, for providing fellowship.


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Authors and Affiliations

  1. 1.Department of Physical SciencesCentral University of PunjabBathindaIndia

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