In situ forming LiF nanodecorated electrolyte/electrode interfaces for stable all-solid-state batteries

The unstable solid electrolyte/electrode interface with dendrite growth and resistance increase significantly reduces the safety and efficiency of all-solid-state batteries. Here, we propose an 'in situ LiF nanodecoration' approach to address this issue. By uniform dispersion of ultrafine LiF nanoparticles in amorphous Li2B12H12 matrix that is in situ formed via a solid-state reaction, the resulting composite as electrolyte exhibits favorable Li-ion conductivity (5 x 10(-4) S cm(-1)) with low electronic conductivity (9 x 10(-10) S cm(-1)) at 75 degrees C. More importantly, this composite electrolyte shows superior electrode compatibility by forming stable electrolyte/electrode interfaces, as demonstrated by high Li dendrite suppression capability (critical current density: 3.6 mA cm(-2)) and small interfacial resistance (area specific resistance after 10 cycles: 746 Omega cm(2)) at 75 degrees C, which further enables the stable cycling of Li-LiFePO4 all-solid-state batteries. This work paves a way for using in- situ nanodecoration chemistry for the design of safe and high efficiency all-solid-state batteries. (C) 2020 Elsevier Ltd. All rights reserved.