Exploration on ION Transport and Materials Properties of PEO based KNO3-Salt Complexed Solid Polymer Electrolyte (SPE)

Ion conducting electroactive polymers or polymer electrolytes in thin flexible forms show great technological potentials to fabricate all-solid-state min/micro electrochemical power sources viz. batteries, fuel cells, supercapacitors etc. Pure polymeric materials are known for their poor electrical conductivity and referred to as insulators. However, polymers can be made electroactive i.e. electron, ion and/or mix conducting by complexing / dissolving electronic, ionic and / or both materials. First ion conducting solid polymer was reported in 1973 and subsequently, the first practical battery based on Solid Polymer Electrolyte (SPE) film was demonstrated in 1979 . Since then, wide variety of SPE film materials, involving different mobile ionic species viz. H+, Ag+, Li+, Na+, K+, Mg2+, etc., have been investigated. In the synthesis of majority of SPE films, reported in the past, high molecular weight polar polymer viz. poly (ethylene oxide) PEO has been used commonly / extensively as polymeric host matrix. This is due to the fact that PEO possesses relatively higher electrochemical stability as well as an exceptional ability to dissolve wide variety of salts as compare to other polymers. The polar and flexible main chain dissociates the salt and hence, carrier ions are generated. These ions can migrate through the amorphous region of the polymer via interchain / intrachain segmental motion. This paper reflects Investigations on Ion Transport and Materials Properties of PEO based KNO3 -salt complexed solid polymer electrolyte (SPE) and NANO-composite polymer electrolyte (NCPE) films.