A deep eutectic electrolyte of AlCl3–acetamide for rechargeable aluminum-ion batteries

Abstract

As multivalent ion batteries, aluminum ion batteries (AIBs) have broad application prospects. In addition, with the further development of new electrolytes, deep eutectic electrolytes are expected to become a green, inexpensive, safe, and ideal electrolytic liquid system to replace traditional ionic liquid electrolytic systems commonly used in AIBs. Herein, we prepared an AlCl₃–acetamide (AcAm) electrolyte and systematically analyzed its ion transport capacity at different molar ratios of its components. Consequently, a compositional ratio of 1 : 1.4 of AcAm : AlCl₃ provided the best ion transport capacity, exhibiting an exceptional electrochemical performance with high reversible capacity, excellent rate performance, and excellent cycling performance. The graphite material in the electrolytic liquid system showed a typical charge storage mechanism dominated by diffusion-controlled processes, indicating that the charge storage behavior of the graphite electrode in this type of electrolyte battery is dependent on ion intercalation. Additionally, the main structure of the graphite material showed little to no change during a long electrochemical test cycle, suggesting its high structural stability. This research shows that the amide electrolyte has great potential for electrochemical application and broad application prospect.