High Performance SnO2/C Nanocomposite Cathode for Aluminum-Ion Battery

Rechargeable aluminum-ion batteries have been researched extensively due to their attractive features, such as the abundant aluminum resources and high capacity resulting from the three-electron redox properties. Herein, a porous carbon supported SnO2 nanocomposite is reported as a cathode material for AIBs. The resultant cell exhibits a high discharge specific capacity of 370 mA h g−1 (with an initial value of 434 mA h g−1) at 50 mA g−1. In the cycling performance, the cell retains a stabilized discharge capacity of 72 mA h g−1 after 20 000 cycles with a coulombic efficiency of ∼100% under an ultrahigh current density of 2 A g−1. Owing to the well-defined nanostructure, side reactions and pulverization of active particles can be prevented. The results indicate that the SnO2/C nanocomposite is a favorable cathode material for AIBs and opens up a new opportunity for the design of high-performance AIBs.