Development and characterization of gel electrolytes based on natural polymers for application in electrochromic devices

Abstract

This paper presents a study of gel electrolyte properties that may be applied in electrochromic devices. This research aimed to develop a stable and conductive gel electrolyte capable of dynamically changing light transmission in response to an applied voltage. The tested gels were prepared based on hydroxyethylcellulose, sodium alginate, xanthan gum, sorbitol, glycerol, and conductive salt LiClO₄. During the research, the physicochemical properties of the gels were analysed, including mass change, density, ionic conductivity, and resistance. The optical quality of the gels was evaluated based on light transmission measurements. The conducted tests allowed for the selection of an optically homogeneous, transparent soft gel, free from air bubbles and contaminants. The highest ionic conductivity value obtained was 32.7 mS/cm². The transparency changes observed in the constructed electrochromic device, depending on the type of gel, were from 55% to 90%.