Fabrication and Characterization of Electrospun Pvam/TEOS Based Gel Polymer Electrolyte

Abstract

Gel polymer electrolyte (GPE) is a promising alternative for the toxic and flammable liquid electrolyte in lithium ion batteries because of leak proof, longer shelf life and safety concerns. GPE consists of a porous polymer host and liquid electrolyte saturated within and combines the advantages of both the liquid and solid components [1].In this study, a novel three-dimensional network GPE based on poly(vinyl alcohol)/maleic anhydride/tetraethyl orthosilicate (PVA/MA/TEOS) with polymer fibers were developed. Crosslinked nanofibrous polymer membranes for GPE of various composition were fabricated by UV-electrospinning method. The dual crosslink polymer membranes were obtained after heat treatment of as-prepared polymer nanofibers, due to the condensation of hydrolyzed TEOS. The morphology of the electrospun membranes was studied using scanning electron microscopy as shown in Figure 1. The uniform and well cross-linked nanofibers were formed with addition of 5 and 10% of TEOS.The excellent thermal properties of the membranes were proven using thermal gravimetric analysis. The membranes have an improved porosity and exhibit high uptake when activated with the liquid electrolyte of lithium salt in a mixture of organic solvents, and also show high liquid retention properties. Electrochemical impedance spectroscopy and linear sweep voltammetry testes showed a high conductivity and vide range (up to 5.5 V) electrochemical stability of prepared GPE. Electrochemical performance of the polymer gel electrolyte is evaluated in Li/polymer electrolyte/LiFePO4coin cell with various current density and showed promising results.Figure 1. SEM image of PVA/MA/TEOS fibers with (a) 5% and (b) 10% TEOS Acknowledgements This research was supported by Faculty-development competitive research grant “Development of composite anion exchange membranes with improved chemical and mechanical stability” from Nazarbayev University. Reference s: [1] M. Zhu, J. Wu, Y. Wang, M. Song, L. Long, S.H. Siyal, X. Yang, G. Sui, Journal of Energy Chemistry 37 (2019) 126-142. Figure 1