Quantification of Hydrogen Sulfide Development during the Production of All-Solid-State Batteries with Argyrodite Sulfide-Based Separators
Timon Scharmann, Canel Özcelikman, Do Minh Nguyen, Carina Amata Heck, Christian Wacker, Peter Michalowski, Arno Kwade, Klaus Dröder
Abstract
High Resolution Image Download MS PowerPoint Slide Solid-state batteries are a promising step in the development of battery technology as they could meet the demands for ever-increasing energy and power densities for an increasingly effective electromobility. Within this battery generation, liquid electrolytes are replaced with solid electrolytes. Compared with other solid electrolyte classes, sulfide-based electrolytes exhibit very high ionic conductivities. Due to the high reactivity of sulfides, exposure to elements within the ambient atmosphere is challenging. Various reaction products negatively affect the resulting battery performance and pose a significant health risk due to the formation of toxic hydrogen sulfide (H 2 S). The reactivity of sulfides therefore represents a major challenge for battery cell manufacturing as it requires material-specific and economical conditioning of the process atmosphere. In the present study, an experimental investigation of hydrogen sulfide formation in relation to different production atmospheres on sulfide solid electrolytes is conducted. Sulfide separators are exposed to different atmospheres with defined conditions using an innovative test setup, which allows a correlation of atmospheric conditions with the resulting hydrogen sulfide. The chosen experimental setup is capable of replicating dynamic air fluctuations analogous to lab-scale dry room conditions at dew points ranging from −60 to +20 °C. A possible scaling of production in a dry room atmosphere is discussed within the use case of the Battery LabFactory Braunschweig in order to define an adequate atmosphere for cell manufacturers and working personal. The results reveal high formation rates of H 2 S at dew points higher than −40 °C within atmospheres with a constant air circulation, which is similar to results with enclosed atmospheres from existing literature. This is underlined by the irreversible morphological material changes observed through microscopic imaging. This enables a more precise investigation under real and controllable conditions along with a recommendation for an economically suitable and material-dependent atmosphere in all-solid-state batteries production.