Search

All-solid-state lithium-sulfur batteries (ASSB-LiS batteries) are considered among advanced candidates for next-generation energy storage systems, as they break with restrictions and limitations that liquid electrolytes impose on lithium-ion batteries and lithium-sulfur batteries (LiS-batteries), meaning enhanced safety and higher energy densities. However, investigations under realistic conditions on pouch cell level are challenging, as it is necessary to implement a scalable preparation method for sheet-type cathodes with high sulfur utilization and loading. In this study, a solvent-free process to prepare free-standing cathode sheets with low binder content down to 0.1 wt% PTFE is demonstrated. The contribution of binder and electrolyte on the conversion reaction of sulfur is discussed. Sheet-type cathodes reach nearly theoretical sulfur utilization of 1672 mAh gS-1 and outstanding reversible capacity reten-tion with 72% of initial discharge capacity after 400 cycles by adapting cut-off voltages to the stability window of the electrolyte. Furthermore, an all-solid-state pouch cell is demonstrated using the dry-film cathode, which is suc-cessfully tested for 50 cycles at different C-rates. Thickness monitoring of the cell stack gives fundamental insights into the volume change and breathing behavior of both cathode and anode.

The high gravimetric and volumetric capacity of silicon renders it an attractive anode material for lithium-ion solid-state batteries (SSBs). Herein, the partial lithiation (800 mAh g-1) of cost-attractive silicon microparticles (μm-Si) in half- and full cells versus nickel–rich NCM (LiNi0.9Co0.05Mn0.05O2) with Li6PS5Cl as a solid electrolyte (SE) is investigated. As a consequence of the cathode and anode potential curve evolution determined in a three-electrode SSB cell, the charge cut-off potential of the NCM|SE|μm-Si cells is reduced. Thereby, the capacity retention after 50 cycles is more than doubled from 32% to 71% without active pressure control on the cells. This concept addresses both the volume changes and the availability of the anode material on an industrial scale being necessary for the utilization of silicon anodes for electric vehicles and other applications. NCM|SE|μm-Si cells achieve up to 28% higher volumetric energy densities compared to the conventional graphite anode.