GO-enhanced Gel Polymer Electrolyte for Aqueous Zinc-Ion Batteries

Graphical Through the multiple cross-linking reaction of sodium alginate (SA), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP) and graphene oxide (GO), a hydrated gel polymer electrolyte (GPE) with high conductivity and excellent mechanical property was prepared. As an additive, GO formed strong hydrogen-bonding interaction with polymers to build a three-dimensional network structure which facilitated the migration of ions and improved the mechanical property of GPE. Aqueous zinc-ion batteries (AZIBs) assembled with gel polymer electrolyte (GPE) have gained great popularity due to their low cost and safety. Nevertheless, the extensive utilization of GPE based AZIBs is hindered by various challenges, such as inadequate conductivity, limited mechanical strength, and unstable electrochemical properties. Herein, through the multiple cross-linking reaction of sodium alginate (SA), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP) and graphene oxide (GO), a hydrated GPE with high conductivity and excellent mechanical property was prepared. GO formed strong hydrogen-bonding interaction with polymers to build a three-dimensional network structure for ion migration and improved the mechanical property of GPE. The prepared GPE showed high ionic conductivity of 2.89×10 −3 S cm −1 and excellent tensile strength of 900 kPa. In addition, the assembled Zn−Li hybrid battery provided a discharge specific capacity retention rate of 67.6 % and a Coulombic efficiency (CE) of approximate 100 % after 1000 cycles at 1 C.