Influence of High Loading on the Performance of Natural Graphite-Based Al Secondary Batteries

In recent years, novel Al secondary batteries with Al anodes, natural graphite cathodes, and ionic liquid electrolytes have received more attention. However, most research on Al secondary batteries used lower graphite loading (<8 mg/cm 2 ), which will inhibit the batteries from commercialization in the future. Here, we prepared Al secondary batteries using Al anode, low-cost natural graphite cathode, and cheaper ionic liquid electrolyte. The effects of loading (7–12 mg/cm 2 ) on performance were investigated. Based on our observations, graphite-based Al secondary batteries (GABs) using 10 mg/cm 2 graphite electrodes had better performance of 82 mAh/g and 6.5 Wh/L at a current density of 100 mA/g. Moreover, the 10 mg/cm 2 GABs showed a long life of 250 charge–discharge cycles with a high coulombic efficiency of 98% and excellent performance rate up to 1000 mA/g.