Abstract

• Solid polymer electrolytes based on chitosan with different weight percent ratios of zinc acetate have been prepared by the solution cast technique and then the flexible polymer electrolyte film were made. The conductivity and dielectric response of the solid polymer electrolyte systems were studied within the frequency range of 120Hz and 1kHz at room temperature. The conductivity of an electrolyte depends on the ability of the polymer host to solvate the zinc acetate. Polymers with higher dielectric constant will serve the purpose better. The dielectric constant and ionic conductivity follow the same trend with zinc acetate concentration. The dielectric constant is frequency dependent, so that the values of dielectric constant were decreased with increasing frequency. The sample containing 30 wt.% exhibited the highest room temperature conductivity of 2.44 × 10-9 S cm-1 , dielectric constant of 2.87 × 10-6 at 120Hz and 4.84 × 10-7 at 1kHz. Structural changes and complex formations of the polymer-salt systems were ascertained from x-ray diffraction (XRD). In order to check the suitability of the solid polymer electrolyte for its application in energy storage devices, polymer capacitor has been fabricated by sandwiching a separator sheet containing the electrolyte between two electrodes. The overall capacitance has been found to be of the order of 19.8 mF at the operating voltage 0.63 V.