High performance aluminum ion battery using polyaniline/ordered mesoporous carbon composite

Abstract

Aluminum-ion battery (AIB) is intriguing for electrochemical power sources due to its potentially high capacity and high safety. However, the most investigated graphitic and metal dichalcogenide cathode materials normally possess moderate capacity and inferior cycling stability, respectively, which limit the performance of current AIBs. Here, we develop a polyaniline (PANI)/ordered mesoporous carbon (OMC) composite as a cathode material of AIB using chloroaluminate ionic liquid as an electrolyte. During the charging/discharging process, two obvious platforms are observed at high voltages of 1.1 V and 1.5–1.7 V. The PANI/OMC cathode exhibits outstanding performance in terms of high specific capacity (140 mAh g−1 at 100 mA g−1), good rate performance (118 mAh g−1 at 2000 mA g−1) and excellent cycling stability (only 12% loss of capacity after 5000 cycles). Based on the ex-situ characterizations, the charge storage of PANI is found to be via the doping/de-doping of anions such as AlCl4−.