Rechargeable Lithium-Hydrogen Gas Batteries.

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/H on the cathode and Li/Li on the anode. The universal properties of the H cathode enable the battery to demonstrate attractive electrochemical performance, including high theoretical specific energy up to 2825 Wh kg, discharge voltage of 3 V, round-trip efficiency of 99.7 %, reversible areal capacity of 5-20 mAh cm, 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. This work presents a route to design batteries based on catalytic hydrogen gas cathode for high-performance energy storage applications.