Characterization of ion transport property in hot-press cast solid polymer electrolyte (SPE) films: [PEO: Zn(CF3SO3)2

Abstract

Characterization of ion transport property in dry solid polymer electrolyte (SPE) films: [PEO: Zn(CF3SO3)2] in different salt wt% ratio has been reported. SPE films have been prepared by a hot-press casting procedure. Salt concentration dependent conductivity study at room temperature identified SPE film: [90PEO: 10 Zn(CF3SO3)2] as optimum conducting composition (OCC) with σ rt ~ 1.09 × 10−6 S/cm which is approximately three orders of magnitude higher than that of pure PEO host (σ rt ~ 3.20 × 10−9 S/cm). The reason attributed for σ rt enhancement has been the increase in degree of amorphous phase in polymeric host after salt complexation. This has been confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and polarized optical microscopy (POM) analysis. To evaluate the usefulness of SPE OCC film in all-solid-state-battery applications, ion transport property has been characterized in terms of basic ionic parameters viz. ionic conductivity (σ) and total ionic (t ion)/cation (t +) transport numbers. Mechanism of ion transport has been explained by temperature dependent conductivity measurements and the activation energy (E a) has been computed by least square linear fitting of “log σ − 1/T” Arrhenius plot.