Studies on a novel microporous electrospun poly(vinyl alcohol)‐based polymer electrolyte membranes for high‐performance battery applications
Authors: Gul Rahmat , Mahmood Wan Ahmad Kamil 
Published: September 2023

INTRODUCTION

Solid polymer blend electrolytes are scientifically interesting promising materials as electrolytes in advanced solid state electrochemical devices applications such as batteries, electrochemical display devices, smart windows, etc. The solid polymer blend electrolyte has several advantages including high energy density, a solvent free condition, structural stability, light weight, leak proof, good electrode electrolyte contact, ease of fabrication, easy processability and good mechanical properties.

OBJECTIVES

The present research work deals with the study of composition and conductivity behavior of polymer blend electrolyte complex membranes based on PVA and PVP complexed with different weight percent KClO4 salt, prepared by electrospinning technique. The resultant polymer blend electrolytes have been characterized by XRD, FTIR and AC conductivity studies.

METHODS

Porous PVA based nanofiber membranes were prepared using a typical electrospinning technique with a horizontal arrangement. A stainless steel needle (24 G, outer diameter: 0.50 mm, inner diameter: 0.35 mm) was connected to an electrode of a high voltage power supply (Spellman, model CZE1000R) which could generate positive DC voltages up to 30 kV and a grounded stainless steel plate was placed at 10 cm distance from the needle tip to collect the nanofiber membranes.

RESULTS AND DISCUSSION

A novel electrospun polymer electrolyte membranes comprising a blend of poly (vinyl alcohol) (PVA) and poly (vinyl pyrrolidone) (PVP) containing various concentrations of potassium perchlorate KClO4 salt are prepared using electrospinning technique. The structure and complexation of the polymer electrolyte membranes have been confirmed from X‐ray diffraction (XRD) and Fourier transform infrared (FTIR) spectral studies. The ac conductivity studies are performed to measure the ionic conductivity of the polymer electrolyte complex systems in the temperature range 298‐353 K and it is also found that the temperature dependence ionic conductivity data seems to follows the Arrhenius relation. The influence of complex membranes composition on the ionic conductivity has been discussed. The maximum ionic conductivity value is obtained to be 9.1×10−4 S cm−1 at 298 K for PVA‐PVP‐KClO4 (50‐35‐15) polymer system with 15 wt.% KClO4 salt. Scanning electron microscopy studies have been performed and reported.

CONCLUSIONS

Free standing, flexible complex polymer electrolyte membranes based on various compositions of PVA‐PVP‐KClO4 have been prepared. The presence of amorphous regions due to complexation of polymer salt matrices has been confirmed from XRD and FTIR analysis. The maximum value of ionic conductivity has been obtained to be 9.1 × 10−4 S cm−1 at 298 K for PVA‐PVP‐KClO4 (50‐35‐15) complex polymer electrolyte system with 15 wt.% KClO4. The excellent performance, such as high values of ionic conductivity, of polymer blend electrolyte membranes suggest that the membranes can be used as the best candidate for high performance solid state batteries.