Artificial Solid Electrolyte Interphase for Sodium Metal Batteries: Mechanistic Insights and Design Strategies

As the transition to renewable energy accelerates, sodium metal batteries have emerged as a viable and economical substitute for lithium‐ion technology. The unstable solid electrolyte interphase on sodium metal anodes continues to provide a significant challenge to attaining long‐term cycle stability and safety. Natural solid electrolyte interphase layers frequently demonstrate inadequate mechanical integrity and deficient ionic conductivity, resulting in dendritic formation, diminished Coulombic efficiency, and capacity degradation. Creating artificial solid electrolyte interphases has emerged as an essential remedy to address these restrictions. This review offers an extensive analysis of artificial solid electrolyte interphases techniques for sodium metal batteries, emphasizing their creation mechanisms, material selection, and structural design. The research highlights the significance of fluoride‐based materials, multi‐layered solid electrolyte interphase structures, and polymer composites in mitigating dendrite development and improving interfacial stability. Advanced characterization techniques, including microscopy and spectroscopy, are emphasized for examining the microstructure and ion transport properties of artificial solid electrolyte interphases layers. Additionally, density functional theory simulations are examined to forecast ideal material compositions and ion migration paths. This study seeks to inform future developments in artificial solid electrolyte interphases engineering to facilitate enhanced performance, safety, and market viability of sodium metal batteries. Artificial solid electrolyte interphases facilitate next‐generation sustainable energy storage systems through new interface designs and integrated analysis.