Conductivity, thermal and morphology studies of PEO based salted polymer electrolytes

Polymer electrolyte has been prepared via solution-casting technique. The polymer electrolytes are formed from polyethylene oxide (PEO) and lithium hexafluorate is used as the doping salt. The conductivity increases from 10−9 to 10−4 S cm−1 upon the addition of various concentrations of salt. The results reveal that the conductivity increases with increasing temperature when the salt concentration increases up to 20 wt% The conductivity for 20 wt% of salt remains similar to the conductivity for 15 wt% of salt at 318 K. Differential scanning calorimetry studies show that the melting transition temperature and crystallinity decreases upon the addition of various concentrations of salt. Thermogravimetric analysis (TGA) results indicate that a significant effect on the thermal stability of polyethylene–lithium salt composites. SEM images reveal that the morphology of polymer electrolyte's surface changes when various concentrations of salt are added into the polymer system.

Impedance plots of samples containing (a) 0 wt%. (b) 5 wt%. and 10 wt%. (c) 15 wt%. and 20 wt%. LiPF6.Figure optionsDownload as PowerPoint slideHighlights
► Polymer electrolyte have been prepared via solution-casting technique.
► The conductivity increases from 10−10 to 10−5 S cm−1 upon the addition varies concentrations of salt.
► TGA results showed a significant effect on the thermal stability of polyethylene–lithium salt composites.
► SEM micrographs show an increase in surface roughness upon the addition of 20 wt% of LiPF6.