Designing Highly Packed Silicon Anode Slurries for High Capacity and Prolonged Lifespan of Lithium-Ion Batteries

Despite its high theoretical specific capacity, silicon (Si) poses certain challenges including large volume expansion and thick solid-electrolyte-interface (SEI) layer formation during the charge/discharge process. This study investigates the crucial role of interparticle interactions and particle packing densities, uncovering their significance in enhancing the coating abilities of Si anode slurries and improving the energy capacity and life cycle of LIBs. A microrheolgical model is employed to predict the rheological properties of Si anode slurries based on their packing densities. We find that a combination of Si nanoparticles (SiNPs) of varying sizes not only augments the energy capacity and slower SEI formation, but also promotes a uniform slurry coating on the electrode. We quantify the coating characteristics of Si anode slurries using dimensionless structural and deformation parameters, thus providing a robust foundation for future advancements in the preparation of LIB slurries.