Semi-Interpenetrated Polymer Networks Based On Modified Cellulose and Starch As Gel Polymer Electrolytes For High Performance Lithium Ion Batteries

Abstract Poly(ethylene oxide) (PEO) is one of the most famous polymer electrolytes; however, its low conductivity and capacity have prevented its commercial applications. This study utilizes carboxymethyl starch (CMS) and oxidative carboxymethyl cellulose (OCMC) natural polymers with a high potential to dissolve lithium ions (Li+) in to help PEO ionic conductivity. The semi-interpenetrating polymer networks (semi-IPNs) consist of crosslinked poly(ethylene glycol) methyl ether methacrylate (PEGMA) with poly(ethylene glycol) diallyl (PEGDA) and free CMS/OCMC chains. Effect of increasing the amount of natural polymer on the electrochemical properties of semi-IPNs is investigated. Semi-IPN CMS50% and semi-IPN OCMC50% deliver excellent results such as high conductivity (in order 10-2 Scm-1) at room temperature, electrochemical stability window higher than 4.5 V, high Li+ transfer number, high discharge capacities (191 and 203 mAh g–1 with capacity retention of 85 and 88.5% after 100 cycles at 0.2 C, respectively), and stable cyclic behavior.