State-of-the-Art Electrolytes and Interfaces Engineering for High-Energy-Density All-solid-State Sodium Batteries

All solid-state sodium batteries (ASSBs) have emerged as a revolutionary energy storage architecture, widely regarded as the most powerful competitor for next-generation battery systems due to their high security, superior energy density, and the inherent economic advantages of sodium resources. Notwithstanding these merits, the commercialization of ASSBs continues to face several challenges that hinder practical implementation, such as the low chemical stability of sodium-ion solid-state electrolytes (SSEs), the poor interfacial contact. In previous studies, researchers have often focused on enhancing the ionic conductivity of SSEs, often ignoring the major challenge of compatibility between SSEs and electrodes to ensure effective interfacial contact. Herein, this review comprehensively summarizes the advancements and ion transport mechanisms of SSEs. Furthermore, the interface challenges faced by ASSBs are also summarized. Aiming at the challenges of the solid-solid interface, the modification strategies are reviewed to improve the interface compatibility and intimacy with the construction suggestions. Finally, the development direction of artificial interface engineering and the prospect of ASSBs are discussed. This review not only serves as a valuable resource for grasping the interfacial science of ASSBs but also provides theoretical guidance for their practical applications.