Electrochemical Lithium Insertion/Extraction for Carbon Electrodes in FSI-based Ionic Liquids

摘要

Introduction of bis(fluorosulfonyl)imide (FSI) as an anion to an ambient-temperature ionic liquid electrolyte based on l-ethyl-3-methylimidazolium and lithium (Li) as cations can provide a reversible Li intercalation into a graphitized electrode, while the intercalation is completely irreversible without FSI. Laser desorption/ionization mass spectroscopy and ac impedance spectroscopy suggest that FSI-coordinated Li~+ is facilely mobile even without any solvents and is reversibly accessible to a graphite interior.