Aluminum Bis(trifluoromethanesulfonyl)imide as a Chloride-Free Electrolyte for Rechargeable Aluminum Batteries

Abstract

Aluminum bis(trifluoromethanesulfonyl)imide (Al(TFSI) 3 ) was synthesized by a simple substitution reaction and investigated as the Al 3+ source for the electrolyte of a rechargeable Al battery. The electrochemical window was extended to 3.6 V with the electrolyte containing Al(TFSI) 3 in AN, whereas it was ∼2.5 V with the conventional electrolyte for the Al rechargeable battery. A reversible electrochemical Al deposition/dissolution reaction was observed on a Mo plate electrode with small overpotential less than 0.5 V. NMR and Raman spectra identified the main Al species in the electrolyte as Al(TFSI − ) x (AN) 6-x 3-x (x = 1 ∼ 6).

Water in Rechargeable Multivalent‐Ion Batteries: An Electrochemical Pandora's Box

“…Non‐chloride electrolytes have also been reported for Al‐ion batteries, including aluminum bis(trifluoromethanesulfonyl)imide, which exhibits a voltage window of 3.6 V (in acetonitrile solvent) and aluminum trifluoromethanesulfonate, which exhibits a voltage window of 3.5 V (in N ‐methylacetamide/urea) . The use of sulfate‐based electrolytes creates pitting corrosion on Al metal, whereas the use of nitrate‐based electrolytes protects Al metal, albeit at the expense of ion‐selective transport .…”

“…[104] Nonetheless,w ater has been shown to inhibit dendrite formationi nN ie lectrodepositionb yu sing choline chloride/urea mixtures, which display ac ompact andc orrosion-resistant electrodeposited film by using an electrolyte containing 6wt% water. [105] Non-chloridee lectrolytes have also been reported for Al-ion batteries, including aluminum bis(trifluoromethanesulfonyl)i- mide, whiche xhibits av oltage window of 3.6 V( in acetonitrile solvent) [106] and aluminumt rifluoromethanesulfonate, which exhibits av oltage window of 3.5 V( in N-methylacetamide/ urea). [107] The use of sulfate-based electrolytes creates pitting corrosion on Al metal, whereas the use of nitrate-based electrolytesprotects Al metal, albeit at the expense of ion-selective transport.…”

Analytical Measurements to Elucidate Structural Behavior of 2,5‐Dimethoxy‐1,4‐benzoquinone During Charge and Discharge

“…Moreover, the use of organic compounds as electrode materials is also promising . Using charge carriers other than Li ions, such as sodium, potassium, magnesium, calcium, aluminum, or molecular ions, is another method to develop sustainability in society. The development of systems that are completely free of scarce metal elements, including a scarce metal‐free charge carrier, will have a significant impact in a society that is heavily dependent on electricity and its consumption.…”

Paving the Path toward Reliable Cathode Materials for Aluminum‐Ion Batteries

“…Besides, in the ionic liquids, the absence of Al cations and instead presence of Al‐based anions may defile the kinetics of cathode reactions, as detailed previously. Then the development of new electrolytes for AIBs would be inspiring, broaden the contents of RAB systems and replenish aluminum‐ion insertion electrochemistry . The new electrolytes targeting the realization of reversible aluminum deposition, are supposed to own high Al‐ion conductivity, broad electrochemical window.…”