Improving electrochemical performance of poly(vinyl butyral)-based electrolyte by reinforcement with network of ceramic nanofillers

This study has concerned the development of polymer composite electrolytes based on poly(vinyl butyral) (PVB) reinforced with calcinated Li/titania (CLT) for use as an electrolyte in electrochemical devices. The primary aim of this work was to verify our concept of applying CLT-based fillers in a form of nano-backbone to enhance the performance of a solid electrolyte system. To introduce the network of CLT into the PVB matrix, gelatin was used as a sacrificial polymer matrix for the implementation of in situ sol-gel reactions. The gelatin/Li/titania nanofiber films with various lithium perchlorate (LiClO4) and titanium isopropoxide proportions were initially fabricated via electrospinning, and ionic conductivities of electrospun nanofibers were then examined at 25 degrees C. In this regard, the highest ionic conductivity of 2.55 x 10(-6) S/cm was achieved when 10 wt% and 7.5 wt% loadings of LiClO4 and titania precursor were used, respectively. The nanofiber film was then calcined at 400 degrees C to remove gelatin, and the obtained CLT film was then re-dispersed in solvated PVB-lithium bis(trifluoromethanesulfonyl)imide (PVB-LiTFSI) solution before casting to obtain reinforced composite solid electrolyte film. The reinforced composite PVB polymer electrolyte film shows high ionic conductivity of 2.22 x 10(-4) S/cm with a wider electrochemical stability window in comparison to the one without nanofillers.