JFET_V12_N3_RP4 Rajiv Kumar Journal on Future Engineering and Technology 2230 – 7184 12 3 28 34 Conductivity, Electrolytes, Fumed Silica, Viscosity, DSC Non-aqueous nano-composite polymer gel electrolytes using Ethylene Carbonate (EC), Ammonium Thiocyanate (NH SCN), Polymethylmethacrylate (PMMA), and Nano-sized Fumed Silica (SiO ) have been synthesized and 4 2 characterized by ionic conductivity, pH, viscosity, and Differential Scanning Calorimetry (DSC) studies. Liquid electrolytes were prepared by dissolving NH SCN in ethylene carbonate, then gel electrolytes were obtained by adding PMMA (wt.% 4 of liquid electrolytes) along with continuous stirring. Nano-composite polymer gel electrolytes were then prepared by adding fumed silica in polymer gel electrolytes. The increase in conductivity with the addition of salt has been explained to be due to an increase in free ions concentration by dissociation of salt which is supported by pH measurements. With the addition of PMMA, the conductivity of the electrolytes decreases, that has been explained due to an increase in viscosity of the electrolytes. The conductivity again shows an increase by small amount, when nano-sized fumed silica was added to gel electrolytes, which is due to facilitation of free ions between high conducting interfacial layers formed by fumed silica. The thermal stability of nano-composite polymer gel electrolytes has been checked by DSC studies. The o conductivity of nano-composite polymer gel electrolytes does not show much change over 30-100 C temperature range and also remains constant with time, which is desirable for advanced electrochemical devices like proton batteries, fuel cells, supercapacitors, and other electrochromic devices. February - April 2017 Copyright © 2017 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=13435