Kinetics‐Reinforced Mechano‐Electrochemically Stable Lithium–Silicon–Nitrogen Composites toward Dendrite‐Free all‐Solid‐State Batteries

Abstract All‐solid‐state lithium batteries (ASSLBs) hold great promise to develop high‐energy‐density and safety secondary batteries, but suffer from the fundamental obstacles of interfacial mechano‐electrochemical instabilities and lithium (Li) dendrite growth. Herein, a kinetics‐reinforced mechano‐electrochemical stable lithium—silicon–nitrogen composites (LSN), is developed, which can effectively promote the interfacial stabilities and suppress Li dendrite propagation. With the integration of silicon, interfacial electrochemical stability is significantly improved by cutting down the potential difference between the Li 6 PS 5 Cl solid electrolyte and LSN. The participation of nitrogen accelerates the kinetic process of Li diffusion, which mitigates concentration polarization and reduces the interfacial overpotential. Simultaneously, interfacial contact loss has been successfully restricted due to the upholding of the Li 4.4 Si & Li 3 N framework. The mechanical, electrochemical, and kinetical reinforced Li 6 PS 5 Cl/LSN interface enables a high critical current density of 15.2 mA cm −2 (50 °C), and a stable cycling of ASSLBs (70.11% capacity retention after 500 cycles), thus overcoming the instinct drawbacks of lithium metal anode and establishing a scalable design principle for dendrite‐free ASSLBs.