Multiscale Design Strategies of Interface‐Stabilized Solid Electrolytes and Dynamic Interphase Decoding from Atomic‐to‐Macroscopic Perspectives

Abstract Solid‐state lithium metal batteries (SSLMBs) are poised to revolutionize energy storage technologies, delivering unparalleled energy density and intrinsic safety through the elimination of flammable liquid electrolytes. Nevertheless, the transition from laboratory breakthroughs to commercial viability is critically impeded by persistent interfacial dilemmas, including lithium dendrite propagation, parasitic chemical/electrochemical degradation at electrode/electrolyte interfaces, and insufficient interfacial contact intimacy. This review systematically and comprehensively reviews the design strategies of interface‐stabilized solid electrolytes, covering inorganic solid electrolytes, solid polymer electrolytes, and inorganic‐polymer composites. The review further decodes the dynamic interplay between the microstructure of solid electrolytes, interfacial ion transport kinetics, and interphase evolution through emerging in situ/operando characterization techniques. By elucidating structure‐property‐interphase relationships across atomic‐to‐macroscopic scales, this review unveils mechanistic insights into the dynamic interfacial evolution and interfacial failure modes over multi‐length scales. Finally, a forward‐looking perspective on interface‐stabilized solid electrolytes is proposed, thereby paving the way for the practical realization of SSLMBs.