A Computational Workflow for the Simulation of Solid State Battery Electrodes from Manufacturing to Electrochemical Performance

All-solid-state lithium batteries (ASSBs) have the potential to deliver higher energy and power densities compared to conventional lithium-ion batteries with liquid electrolytes. Due to the use of solid electrolytes, a uniform distribution and close contact between the active material (AM) and solid electrolyte (SE) particles are essential for a proper electrochemical behavior of the electrodes. Thus, understanding the correlation between the microstructure of composite electrodes, charge transport, and cell performance is critical. The composite cathode microstructure composed of Li6PS5Cl and NCM622 obtained from the simulation of its wet manufacturing process is used to implement a 4D (3 spatial coordinates, and time) computational model that simulates the electrochemical behavior during an ASSB cell discharge. The study explores the effect of the conventional calendering technique during manufacturing, demonstrating that the spatial distribution of phases and the presence of residual voids significantly influence percolation, impacting ionic and electronic conduction as well as the electrochemically active surface area. Consequently, these factors dictate the overall performance of the ASSB cell. Our findings highlight the importance of a homogeneous, compact cathode microstructure for achieving optimal ion and electron transport, ultimately enhancing the performance of ASSB cells.