Rechargeable Lithium‐Hydrogen Gas Batteries

Abstract The global clean energy transition and carbon neutrality call for developing high‐performance batteries. Here we report a rechargeable lithium metal ‐ catalytic hydrogen gas (Li−H) battery utilizing two of the lightest elements, Li and H. The Li−H battery operates through redox of H 2 /H + on the cathode and Li/Li + on the anode. The universal properties of the H 2 cathode enable the battery to demonstrate attractive electrochemical performance, including high theoretical specific energy up to 2825 Wh kg −1 , discharge voltage of 3 V, round‐trip efficiency of 99.7 %, reversible areal capacity of 5–20 mAh cm −2 , all‐climate characteristics with a wide operational temperature range of −20–80 °C, and high utilization of active materials. A rechargeable anode‐free Li−H battery is further constructed by plating Li metal from cost‐effective lithium salts under a low catalyst loading of <0.1 mg cm −2 . This work presents a route to design batteries based on catalytic hydrogen gas cathode for high‐performance energy storage applications.