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Rechargeable Li−Cl2 battery is a promising high energy density battery system. However, reasonable cycle life could only be achieved under low specific capacities due to the sluggish oxidation of LiCl to Cl2. Herein, we propose an amine‐functionalized covalent organic framework (COF) with catalytic activity, namely COF−NH2, that significantly decreases the oxidation barrier of LiCl and accelerates the oxidation kinetics of LiCl in Li−Cl2 cell. The resulting Li−Cl2 cell using COF−NH2 (Li−Cl2@COF−NH2) simultaneously exhibits low overpotential, ultrahigh discharge capacity up to 3500 mAh/g and a promoted utilization ratio of deposited LiCl at the first cycle (UR−LiCl) of 81.4 %, which is one of the highest reported values to date. Furthermore, the Li−Cl2@COF−NH2 cell could be stably cycled for over 200 cycles when operating at a capacity of 2000 mAh/g at −20 °C with a Coulombic efficiency (CE) of ≈100 % and a discharge plateau of 3.5 V. Our superior Li−Cl2 batteries enabled by organocatalyst enlighten an arena towards high‐energy storage applications. [ABSTRACT FROM AUTHOR]

Metallic zinc (Zn) is considered as one of the most attractive anode materials for the post‐lithium metal battery systems owing to the high theoretical capacity, low cost, and intrinsic safety. However, the Zn dendrites and parasitic side reaction impede its application. Herein, we propose a new principle of regulating p‐band center of metal oxide protective coating to balance Zn adsorption energy and migration energy barrier for effective Zn deposition and stripping. Experimental results and theoretical calculations indicate that benefiting from the uniform zincophilic nucleation sites and fast Zn transport on indium tin oxide (ITO), highly stable and reversible Zn anode can be achieved. As a result, the I−Zn symmetrical cell achieves highly reversible Zn deposition/stripping with an extremely low overpotential of 9 mV and a superior lifespan over 4000 h. The Cu/I−Zn asymmetrical cell exhibits a long lifetime of over 4000 cycles with high average coulombic efficiency of 99.9 %. Furthermore, the assembled I−Zn/AC full cell exhibits an excellent lifetime for 70000 cycles with nearly 100 % capacity retention. This work provides a general strategy and new insight for the construction of efficient Zn anode protection layer. [ABSTRACT FROM AUTHOR]