Strategies of constructing highly stable interfaces with low resistance in inorganic oxide-based solid-state lithium batteries

Oxide solid-state electrolytes (OSEs) with high ionic conductivity, wide electrochemical window and inherent safety are critical to achieve high-energy-density and safe performance of solid-state batteries (SSBs). However, the large interfacial impedance and severe side reactions between OSEs and electrodes remain challenging for ion transport in SSBs, which is attributed to the poor physical contact and chemical compatibility between OSEs and electrode materials. In this review, the recent research on solid-state interfaces in SSBs is summarized and discussed. These strategies can be categorized into interfacial structure design and interfacial modifications. Structure designs, including constructing architectural Li anode, three-dimension (3D) structure OSEs and integrated cathode can significantly increase the effective contact area between electrodes and OSEs to facilitate the interfacial ion transport. The interfacial modifications are utilized to improve the wettability of OSEs for lithium metal anode, enhance the interfacial ion transport, and stabilize the OSEs/electrodes interface. Interface architecture is crucial to enhance structural stability and reduce interface impedance for advanced oxide-based SSBs. At last, the future research direction of interfacial modification in SSBs is prospected.