Solid-state batteries (SSBs) are considered an upcoming alternative to currently commercially available Lithium-ion batteries (LIBs) employing liquid electrolytes. Advantages of SSBs include increased energy density and increased safety compared to LIBs. Within a SSB, the liquid electrolyte and polymer separator in LIBs are replaced with an ion-conducting solid functioning as both the electrolyte and separator, thereby eliminating flammable organic solvents from the battery cell. Furthermore, due to the increased mechanical stability, the solid electrolyte is considered to inhibit Lithium dendrite growth. This enables Lithium metal as anode material boosting the energy density of SSBs.
However, the third crucial component in the SSB is the cathodic electrode. Here, both ionic and electronic pathways need to be optimised while maximising the active material amount to ensure full utilisation of the active material as well as high energy density. Since the replacement of liquid electrolyte with a solid alternative eliminates the possibility of infiltrating the porous structure upon the electrolyte filling step, the solid electrolyte material needs to be added into the cathode mixture during electrode production prior to cell assembly. While production steps may be adapted from the LIB production, especially investigation of process steps mixing and coating is still necessary to correlate process parameters to battery cell performance results and optimise the SSB production.
In this presentation, the fabrication of a composite cathode comprising of active material LiFePO4and a solid polymer electrolyte based on a reactive polymer is demonstrated. Slurries are prepared by mixing the educts and additives, e.g. conductive carbon.

The slurry is then coated onto an Aluminium current collector using doctor blade method. During the drying step, the polymerisation is initiated, creating the polymer electrolyte. Mixing and coating parameters are varied. The resulting cathodes are characterised regarding their morphology, dry film thickness and mass loading. Electrochemical performance is evaluated in half cell setup employing a Lithium metal anode.