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Lithium metal has a low redox potential (-3.04 V vs standard hydrogen electrode) and high specific capacity (3860 mAh/g), making it an ideal anode material for lithium secondary batteries. The solid-state lithium battery assembled by metal lithium negative electrode/solid electrolyte/lithium-inserted positive electrode is expected to become the power source of related technology industries such as aerospace, robotics, high-end electronics and electric vehicles in the future. However, during the charging and discharging process, due to the uneven deposition and dissolution of lithium, a large number of dendrites are produced on the contact surface between lithium and the electrolyte, and they continue to grow along the direction of the electrolyte, eventually causing the internal short circuit and failure of the battery. The use of a solid electrolyte with a higher Young’s modulus can block the growth of lithium dendrites to a large extent, but still cannot meet the requirements of battery long-term cycling and safety. In addition, metal lithium is in solid-solid contact with the solid electrolyte surface, causing problems such as high electrical resistance across the interface and interfacial reaction between metal lithium and solid electrolyte, which severely hinders the development and use of solid lithium metal batteries. The strategies for inhibiting the growth of lithium dendrites and improving the compatibility of solid-solid interface in metal lithium batteries based on solid electrolytes in recent years were reviewed in this article, and prospects for future development on the interface engineering of Li metal and solid-state electrolytes were prospected.

Compared with traditional lithium-ion batteries, all-solid-state lithium-metal batteries (ASS LMBs) have attracted much attention due to their high safety and high energy density. However, the solid-solid contact of electrodes with solid electrolyte brings large interfacial impedance. Besides, the active lithium metal reacts with most solid electrolytes,leading to unstable interface. So interfacial problem has been one of the key issues to limit the development of ASS LMBs. Solid composite electrolytes with the advantages of inorganic solid electrolytes and organic solid electrolytes, have higher ionic conductivity and certain mechanical strength, showing excellent promising in the light of practical application. The research progress on interface amelioration of solid composite electrolyte and lithium anode was summalized in this review. The main strategy includes constructing a "soft contact" at the interface, adjusting the mechanical performance of the solid electrolyte and tuning the deposition dynamics of lithium ions. Furthermore, the perspectives on interfacial modification were presented.