Towards a practical use of sulfide solid electrolytes in all-solid-state-batteries: Impact of dry room exposure on H2S release and material properties

International audienceAll-solid-state-batteries studies have increased steadily over the past few years. One family of materials gaining particular attention are the moisture sensitive sulfide solid electrolytes, mostly because of their impressive ionic conductivity and their cyclability in lithium-based batteries. Even though we witness a strong interest from batteries and cars manufacturers leading to several partnerships to accelerate the technology development, the literature is mostly dominated by lab scale concerns. In most studies, solid-state-batteries are manufactured in a glove box in order to prevent the exposition of solid electrolytes to moisture. Herein, we propose a study on three sulfide electrolytes, namely in-house Li7P3S11 and Li5.8PS4.8Cl1.2 along with commercial Li6PS5Cl, in a dry room environment (dew point = -40 °C), in order to elucidate 1. the safe handling of sulfide electrolytes regarding its propensity to generate H2S and 2. the resulting material properties after dry room exposure thanks to a set of characterization techniques including X-ray diffraction, Raman spectroscopy, electrochemical impedance spectroscopy, scanning electron microscopy and X-ray photoelectron spectrometry to hypothesize the potential degradation mechanisms occurring at the particle surface. Finally, galvanostatic cycling of Li0.38In0.62-NMC622 cells will be presented to assess the impact of dry room exposure on cell performance. This work is fundamental to any research projects aiming to find suitable processes to manufacture sulfide-based solid-state-batteries at larger scale