Ionic liquid-based rechargeable lithium metal-polymer cells assembled with Polyaniline/Carbon nanotube composite cathode

A polyaniline (PANI)/multiwalled carbon nanotube (CNT) composite was synthesized by in situ chemical polymerization. The PANI/CNT composite was used as an active cathode material in lithium metal-polymer cells assembled with ionic liquid (IL) electrolyte. The IL-based electrolyte was composed of 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) and vinylene carbonate (VC) as an additive, together with LiBF4. Porous poly (vinylidene-co-hexafluoropropylene) [P(VdF-co-HFP)] film was used as a polymer membrane for assembling the cell. Electrochemical performance of the Li/IL/PANI-CNT cells was evaluated by cyclic voltammetry, ac impedance measurements, and constant-current charge/discharge cycling. Lithium metal-polymer cells assembled with the IL electrolyte showed good cyclability with a maximum discharge capacity of 139 mAh/g and good high-rate performance. (C) 2007 The Electrochemical Society.