In recent years, the metal-CO₂ battery has been demonstrated as a novel approach to capture CO₂ from gas streams and to generate electricity, particularly using high energetic metallic Lithium, Sodium, Magnesium and Aluminum anodes. Aluminum is the most abundant metal in the earth’s crust and is less reactive than alkali metals. Aluminum also participates in a three-electron process during electrochemical charge/discharge reactions, which gives its attractive gravimetric capacity (2980 Ah/kg) and competitive volumetric capacity (804 Ah/cm³) compared to single-electron lithium and sodium redox reactions. A rechargeable metal-CO₂ battery based on aluminum metal is advantageous in terms of cost-effectiveness, manufacturability and safety handling. In this work, we developed an Al-CO₂ battery that is rechargeable and can deliver high capacity and high energy. The battery utilizes an aluminum metal anode, a commercial carbon cathode and an ionic liquid electrolyte containing AlCl₃/1-ethyl-3-methyl imidazolium chloride with a redox mediator as the electrolyte additive. Al-CO₂ cells with this design are shown to achieve excellent rechargeability with less than 50 mV overpotential. Reversible storage capacity of 500 mAh/g based on the active carbon mass on the cathode for over 13th cycles is reported. An ultra-high energy density of 9930 Wh/kg and specific capacity of 9411 mAh/g can be achieved when performing a full discharge at 100% CO₂ gas environment. Importantly, an energy density of 910 Wh/kg and specific capacity of 901 mAh/g can still be reached when the cell is discharged in 5% CO₂ mixed with argon gas. This indicates the cell can probably capture and convert CO₂ directly from the flue gases, while generating and storing electricity. We have been activity studying the fundamental reaction mechanism of the Al-CO₂ batteries by using spectroscopic and electrochemical tools at the cathode during the charge and discharge processes. On that basis, we plan to discover the carbon capture mechanism and improve the electrochemical performance of the rechargeable Al-CO₂ battery.