Sulfonylimide-Based Cation Exchange Membranes As Electrolyte for Lithium-Ion Batteries. Synthesis and Characterization

摘要

The use of cation-exchange membranes as electrolytes in lithium-ion batteries is considered to be one of their highly promising applications. Polystyrene-based membranes containing sulfonylimide functional groups are the promising materials for these application due to the low crystallinity of polymer, high dissociation degree of functional groups, as well as thermal and electrochemical stability of obtained electrolytes. There are two different approaches for the synthesis of sulfonylimide based polymers: polymerization of functional monomer, and functionalization of the polymer. The aim of this work was to synthesize membranes based on polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) containing functional sulfo R-SO_3Li and sulfonylimide groups [R-SO_2NSO_2-X]Li, where X= -CF_3, -CCl_3, -CH_3, -C_6H_5, -p-NO_2C_6H_4 and -p-CF_3C_6H_4, and investigation of Li~+ conductivity of polyelectrolytes solvated by mixtures of ethylene carbonate/dimethylacetamide (EC-DMA) and ethylene carbonate/propylene carbonate (EC-PC). Membranes were synthesized according to the Scheme.