Characterization of nanochitosan incorporated solid polymer composite electrolytes for magnesium batteries

摘要

Introduction Solid polymer electrolytes (SPE) composed of poly (ethylene oxide) (PEO) and lithium salts are extensively studied for their application in novel electrochemical systems such as rechargeable lithium batteries, electrochemical capacitors and sensors. Though the PEO-lithium salt complexes works well, magnesium ions conducting electrolytes are of current interest for its wide scope in the development of rechargeable magnesium polymer batteries in the future. Magnesium is an attractive anode material for batteries of high specific energy because of its low electrochemical equivalence (12.15 g/equiv) and a considerable negative electrode potential (-2.3 V vs SHE). In addition, its cost is low due to natural abundance and it is safer than lithium [1-5]. Despite the advantages of PEO, its room temperature conductivity is 3.57×10~(-9)S/cm [6]. For improving the ionic conductivity of the solid polymer electrolyte (SPE), addition of non-aqueous organic solvents with a low molecular weight as a plasticizer or by adding nanofiller into the matrix polymer has been proposed [7,8]. In the present study, solid polymer electrolytes with PEO as the host polymer, nanochitosan as the filler and with Mg(ClO_4)_2 as the salt have been prepared. The polymer membranes were prepared using membrane hot press. The effect of nanofiller on the ionic conductivity was studied. Surface morphology was studied by SEM analysis and the complexation behavior of PEO and Mg(ClO_4)_2 was verified by FT-IR studies.