Interfacial challenges in all-solid-state lithium batteries

This mini-review provides a current opinion on interfacial challenges in solid-state batteries (SSBs). We focus our discussion on the effects of mechanical instability, chemical instability, electrochemical instability, and space charge layer formation on the interfacial resistance of SSBs. We highlight that the resulting interfacial resistance of SSBs arises from the coupling of all these effects. Quantifying the exact contribution of each effect to the overall interfacial resistance can be very difficult, if not impossible, because all these effects occur simultaneously during battery operation, but the dominant source, which varies with different electrode/electrolyte combinations, will need to be determined for future development of SSBs.