IntelligentStrategy of Lithium Metal Reconstructionthrough Generation of a Protective Layer and Regulating Lithium Deposition

Lithium metal has been considered as the most promising anode for next-generation batteries. However, its high reactivity with electrolyte and the growth of lithium dendrites hamper the application of lithium metal-based batteries. Herein, we demonstrate that lithium polyphosphides (Li_<i>x</i>PPs) can be dissolved in diethyl carbonate (DEC) and used as a reconditioner for generating a protective layer and regulating deposition of the Li metal anode. Since Li_<i>x</i>PPs are reduced prior to Li deposition in the lithiation process, their product can be a uniform and tight layer at the surface of the Li metal. The in situ-formed protection layer has superhigh Li ionic conductivity, and its thickness can be easily controlled by tuning the amount of Li_<i>x</i>PPs, thus facilitating the interface stability. The Li–Li symmetry batteries show stable cycling performance at 2 mA cm^–2 and 1 mAh cm^–2 over 5000 h. Interestingly, it exhibits a self-healing function on scratched Li metal.