Mechano‐Electrochemical Healing at the Interphase Between LiNi0.8Co0.1Mn0.1O2 and Li6PS5Cl in All‐Solid‐State Batteries

Abstract Sulfide‐based all‐solid‐state batteries (ASSBs) are emerging as promising alternatives to lithium‐ion batteries due to their high energy density and enhanced safety. However, sulfide solid electrolytes, such as Li6PS5Cl (LPSCl), face significant chemo‐mechanical challenges at the interface with layered oxide cathodes, including Li[Ni0.8Co0.1Mn0.1]O2 (NCM811). During cycling, oxidative decomposition of LPSCl leads to interfacial void formation and mechanical contact loss, which significantly degrade ionic conduction. Strategies such as coating stable passivation layers have been explored to suppress LPSCl decomposition, but these approaches often involve trade‐offs, including increased cost, complex synthesis, and elevated interfacial resistance. Herein, the concept of mechano‐electrochemical healing at the LPSCl–NCM811 interface is introduced to address these issues. During char…