Highly Conductive Solid Polymer Electrolytes by para-Fluoro/Thiol Clicked Diblock Copolymer Self-Assembly: Paving the Way for Nanostructured Materials for Lithium-Ion Conductivity

A new class of amorphous solid polymer electrolytes (SPEs) based on polystyrene-b-poly(pentafluorostyrene) (PS-b- PPFS) was prepared via nitroxide-mediated polymerization (NMP) followed by introduction of oligomeric polyethylene glycol (PEG) using para-fluoro/thiol click chemistry. Block copolymers (BCPs) with different combinations of PPFS fractions and degrees of PPFS substitution were synthesized, and the morphologies were studied neat and with Li salt using atomic force microscopy (AFM). Among the various block copolymer electrolytes (BCEs) studied, the electrolyte with a 0.69 volume fraction of PPFS-PEG fully substituted with r = [Li/EO] = 0.08 was the best performing solid electrolyte and exhibited ionic conductivity (sigma) from 3.3 x 10-5 to 4.0 x 10-4 S cm-1 at 30 and 70 degrees C, respectively. The results indicate that well-designed and nanostructured PPFS-PEG-based SPEs can be excellent materials for the construction of all-solid-state Li-ion batteries.