The Interface Engineering of All–Solid–State Batteries Based on Inorganic Solid Electrolytes

All–solid–state batteries (ASSBs) based on inorganic solid electrolytes (SEs) are one of the most promising strategies for next–generation energy storage systems and electronic devices due to the higher energy density and intrinsic safety. However, the poor solid–solid contact and restricted chemical/electrochemical stability of inorganic SEs both in cathode and anode SE interfaces cause contact failure and the degeneration of SEs during prolonged charge–discharge process. As a result, the increasing interface resistance significantly hinders the coulombic efficiency and cycling performance of ASSBs. Herein, we present a fundamental understanding of physical contact and chemical/electrochemical features of the ASSB interfaces based on mainstream inorganic SEs and summarize the recent work on interface modification. SE doping, optimizing morphology, introduce interlayer/coating layer and utilizing compatible electrode materials are the key methods to prevent the side reactions which are discussed separately in cathode/anode–SE interface We Also highlight the constant extra stack pressure applied during ASSBs cycling, which is important to the electrochemical performance. Finally, our perspectives of interface modification for practical high–performance ASSBs are put forward.