Dual‐Phase Single‐Ion Pathway Interfaces for Robust Lithium Metal in Working Batteries

-based bottom layer and a lithiated Nafion top layer. The as-constructed artificial solid electrolyte interphase is demonstrated to significantly stabilize the repeated cell charging/discharging process via regulating a facile Li-ion transport and a compact Li plating behavior, hence contributing to a higher coulombic efficiency and a considerably enhanced cyclability of lithium metal batteries. This work highlights the significance of rational manipulation of the interfacial properties of a working Li metal anode and affords fresh insights into achieving dendrite-free Li deposition behavior in a working battery.