Quantitative determination of lithium depletion during rapid cycling in sulfide-based all-solid-state batteries

We propose a promising electrochemical analysis tool based on the distribution of relaxation times (DRT) to quantify interfacial resistances towards a comprehensive understanding of complex solid-state interfacial phenomena in sulfide-based all-solid-state batteries (ASSBs). Using DRT-assisted impedance analysis, we identify a new resistance component in the range of 10²-10³ Hz of 3.5 and 0.9 Ω in the absence and presence of a LiNbO₃ layer, respectively, at 1C-rate. Experimental and computational studies confirm that this interfacial resistance results from lithium depletion in sulfide solid electrolytes. Furthermore, we expect our approach to provide new insights into complex interfacial phenomena in ASSBs.