Scalable Production of Separator and Cathode Suspensions via Extrusion for Sulfidic Solid-State Batteries

Abstract

Due to their high ionic conductivity, sulfidic solid electrolytes are considered to have great potential as a key element of solid-state batteries. Such batteries could offer safety, thermal stability, and high energy densities. A key requirement is the scalable production of separators and electrodes, taking into account the high demands the moisture-sensitive material imposes on the surrounding atmosphere. Therefore, in this publication we will demonstrate the establishment of an extrusion process under argon atmosphere for the continuous production of separator and cathode suspensions. After systematically investigating the influence of the process parameters speed, temperature and mass flow on the adhesive strength, ionic conductivity and capacity, the obtained knowledge is used for the fabrication of improved layers. The Li3PS4 based separators show a comparatively high ionic conductivity of 0.036 mS cm−1 (conductivity of pure solid electrolyte: 0.05 mS cm−1), the cells reach specific capacities of up to 156 mAh g−1 in the 1st cycle.