Electrochemically Exfoliated Graphene Electrode for High-Performance Rechargeable Chloroaluminate and Dual-Ion Batteries

The current state-of-the-art positive electrode material for chloroaluminate ion batteries (AIBs) or dual ion batteries (DIBs) is highly crystalline graphite; however, the rate capability of this material at high discharge currents is significantly reduced by the modest conductivity of graphite. This limitation is addressed through the use of graphene-based positive electrodes which can improve the rate capability of these batteries due to their higher conductivity. However, conventional methods of graphene production induce a significant number of defects which impair the performance of AIBs and DIBs. Herein, we report the use of a defect free graphene positive electrode which was produced using electrochemical exfoliation of graphite in an aqueous solution with the aid of Co2+ as an antioxidant. The Co-treated graphene electrode achieved a high capacity of 150 mAh g-1 in DIBs and 130 mAh g-1 in AIBs with high rate capability for both batteries. The charge-discharge mechanism of the batteries is examined...