An Ionic Liquid‐Surface Functionalized Polystyrene Spheres Hybrid Electrolyte for Rechargeable Zinc/Conductive Polymer Batteries

Abstract A rechargeable zinc/poly(p‐phenylene) (PPP) battery has been fabricated using Zn metal as the anode and electrochemically synthesized PPP as the cathode, with ionic liquid (IL)‐surface functionalized polystyrene (PS) spheres as the electrolyte. The PS spheres were treated with oxygen‐plasma to introduce polar groups (e. g., carbonyl and carbonate) that interact with the components of the IL, enabling the fast movement of the Zn2+ ions upon polarization. The wettability, ionic conductivity and electrochemical performance are thus largely enhanced. The confinement of the IL electrolyte in the PS sphere framework allows the formation of porous and dendrite‐free zinc deposits upon charge/discharge cycling. The voltage profiles are largely improved. The Zn/PPP rechargeable battery exhibits long‐term cycling stability over at least 300 cycles with a Coulombic efficiency of more than 96 %.