A Rechargeable Al/Graphite Battery Based on AlCl3/1‐butyl‐3‐methylimidazolium Chloride Ionic Liquid Electrolyte

Abstract As a new and efficient power storage device, Al‐ion batteries present good prospects due to its many advantages, such as excellent performance and rich resources. In this work, a rechargeable Al‐ion battery system has been fabricated in pouch cell based on a room temperature ionic liquid (RTIL) containing AlCl 3 /1‐butyl‐3‐methylimidazolium chloride (BMIC) as electrolyte. The capacity of the battery is 86.4 mAh g −1 at the 100th cycle at a current density of 50 mA g −1 , and it remains above 78.0 mAh g −1 after 300 cycles. A high discharge voltage platform about 2.15 V vs . Al 3+ /Al is obtained. In addition, in situ X‐Ray Diffraction (XRD) measurements were conducted to confirm the intercalation/de‐intercalation mechanism in the graphite layers. All of these suggest that the Al/graphite battery based on AlCl 3 /BMIC electrolyte, which exhibits an excellent electrochemical performance for energy storage, may be a promising Al‐ion battery system.