Comparative Study on Charge–Discharge Behavior of Graphite Positive Electrode in FSA- and FTA-Based Ionic Liquid Electrolytes with Different Alkali Metal Cations

Dual-carbon batteries (DCBs), in which both the positive and negative electrodes are composed of carbon-based materials, promising next-generation owing to their limited usage scarce metals high operating voltages. In typical DCBs, metal cations anions electrolytes consumed simultaneously at electrodes, respectively, can rapidly deplete charge carrier ions electrolytes. this study, solve challenge, we focused on ionic liquids (ILs) as DCB because they solely therefore intrinsically highly concentrated Charge–discharge behavior graphite was investigated several IL containing alkali (Li + , Na K ) amide (FSA − FTA ; FSA = bis(fluorosulfonyl)amide, (fluorosulfonyl)(trifluoromethylsulfonyl)amide). It found that FTA-based ILs conferred superior cycling stability higher capacities compared FSA-based ILs, explained by suppression corrosion aluminum current collector The highest reversible capacity approximately 100 mAh g −1 obtained for K-ion system using 20 mA involved formation FTA–graphite intercalation compounds, confirmed ex situ X-ray diffraction.