Study on Mg-ion conducting solid biopolymer electrolytes based on tamarind seed polysaccharide for magnesium ion batteries

Abstract

Natural bio-macromolecule tamarind seed polysaccharide (TSP) with magnesium perchlorate (Mg(ClO4)2) salt based Mg-ion conducting solid electrolyte was prepared by solution casting technique. The influence of different concentrations of Mg(ClO4)2 salt on the electrical and electrochemical performances of TSP were systematically investigated. Addition of salt into TSP matrix, change in their structural, vibrational and morphological properties were studied and analyzed through XRD, FTIR and FESEM methods respectively. The TSP with 0.25 (m.m.%) Mg(ClO4)2 salt complex exhibited good thermal stability and high electrochemical window. The TSP with 0.25 (m.m.%) of Mg(ClO4)2 offers a maximum Mg-ion conductivity of 5.66 × 10−4 Scm−1 at ambient temperature with maximum ionic transference number of 0.43. Primary Mg-ion battery was constructed using the highest Mg-ion conducting sample and their operations were explored. The constructed primary battery exhibited the open circuit potential of 2.36 V at room temperature.