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The aim of this research work is to examine the modification of structure, morphology and conductivity properties of PMMA: PEO blend hybrid polymer electrolyte system complexed with NaClO4 salt. Solution-cast procedure was adopted in preparation of these films. These films were characterized with XRD, SEM, DSC, and DC conductivity for the evaluation of modified properties. Peaks have disappeared and broadened in the XRD pattern of PMMA for higher concentration of PEO polymer and salt presented films, which indicated that attaining of higher amorphous phase in these polymer electrolyte films. Almost smooth surface morphology with fewer pores was observed in 20 wt. % of PEO and NaClO4 salt present PMMA films of SEM image. This establishes a dominant presence of amorphous content in these NaClO4 complexed PMMA:PEO hybrid electrolyte films when compared to pure PMMA and PEO. Disappearance of melting temperature was observed in all concentrations of NaClO4 salt and PEO polymer added PMMA polymer films, which suggests a decrease of crystalline and an increase of amorphous nature. Enhancing of DC conductivity with temperature was observed in all the films but higher conductivity was exhibited at higher concentration of NaClO4 salt present films.

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In this paper, solid polymer electrolytes comprising of Poly (vinylidene-fluoride-hexafluoropropylene) (PVDF-HFP) polymer and Mg (ClO4)2 salt were prepared by employing the solution casting technique. The fabricated polymer-salt electrolyte membranes are exposed to XRD, FTIR and SEM studies. The real and imaginary part of dielectric permittivity is illustrated with the Cole-Cole plot. Static dielectric constant \({(\epsilon }_{s})\), dynamic dielectric constant \(\left({\epsilon }_{\infty }\right)\), dielectric strength \(({\Delta }\epsilon\)), dielectric loss (tanδ) and relaxation time (τ) are determined using the Cole-Cole plot. The electrochemical properties; cell stability, cell discharge characteristics, dc and ac conductivity are analyzed. Structural studies of XRD peaks are broadened to confirm the amorphous phase of polymer matrix. Morphological studies shows the presence of interlinked micro-pores promote for ease of mobility of Mg2+ ions which attribute to enhance ionic conductivity. The static dielectric constant \({(\epsilon }_{s})\), dynamic dielectric constant \(\left({\epsilon }_{\infty }\right)\), dielectric strength \(({\Delta }\epsilon\)), dielectric loss (tanδ) reach maximum but relaxation time (τ) decreases for an optimal concentration ratio of (100:40) PVDF-HFP: Mg (ClO4)2 that reveals fast hopping of ions from one site of the polymer chain to another. The highest ionic conductivity of 7.73333x 10− 4 Scm− 1 is obtained at room temperature for [PVDF-HFP: Mg(ClO4)2] polymer-salt electrolyte. The cell discharge characteristics of OCV and SCC of Mg/ [PVDF-HFP: Mg(ClO4)2] /I + C cell are found to be 1.8 V and 120 mA respectively The electrochemical stability was observed with a constant voltage of 0.43volt in a positive cycle and 0.4 volts of negative potential which favors an electrochemical membrane for battery applications