Dynamic Covalent and Ionic Bond Reorganization for Self-Adaptive Interphase Enhancing the Electrochemical Stability of Li₆PS₅Cl with Lithium Anode

All-solid-state batteries (ASSBs) with lithium metal anodes are expected to be one of the most promising energy storage systems to achieve high energy density. However, the interfacial side reactions between lithium anodes and argyrodite electrolytes significantly limit the cycling stability. Herein, a self-adaptive Li–Mg–Cl interphase is constructed in situ through driving the MgCl2 incorporated Li6PS5Cl with an electric field. Ab initio molecular dynamics (AIMD) analysis reveals that the Li–Mg–Cl network undergoes dynamic covalent-ionic bond reorganization, enabling self-anchored interfacial coordination of Li–Mg, Li–Cl, and Mg–Cl. The dynamic bonding of Li–Mg–Cl further exhibits self-healing behavior due to lithophile site, which autonomously repairs structural defects during the (de)lithiation process. Moreover, the interphase regulation inhibits dendrite formation through improving the mobility of Li+ ions. Consequently, the assembled cell operates stably for 1300 h under a current density of 0.1 mA cm–2 at 25 °C. The all-solid-state batteries with LiNi0.8Co0.1Mn0.1O2 as cathode demonstrate outstanding performance, with an initial capacity of 169 mAh g–1 at 0.2 C and a capacity retention of 80% after 100 cycles. The electrolyte modified with an electric field, based on its low-cost and highly energy-efficient features, further promotes the development of sustainable production processes.