Heterogeneities affect solid-state battery cathode dynamics

Solid-state batteries hold the promise to improve energy and power densities compared to conventional lithiumion batteries. Among myriad interface and mechanistic challenges plaguing the solid-state batteries, the composite cathode architecture owing to the underlying microstructural heterogeneity poses a critical bottleneck. The spatial variability of solid-solid point contacts and ionic/electronic percolation pathways govern the underlying reaction-transport dichotomy, and ultimately affect the spatio-temporal dynamics. In this work, we postulate the inherent role of mesoscale interactions and delineate how heterogeneities profoundly affect the spatio-temporal evolution of thermo-electrochemical dynamics subject to physical and operational extremes. This study critically examines the importance of solid-solid point contacts manifesting as singularities in thermoelectrochemical hotspot formation, intercalation cascade, and reaction current localization and establishes these as mechanistic pain points for consideration in the future development of improved solid-state battery cathode architectures.

Automated summary

Solid-state batteries have the potential to improve energy and power densities compared to conventional lithium-ion batteries. The composite cathode architecture, resulting from microstructural heterogeneity, poses a critical bottleneck for solid-state batteries. This study examines the inherent role of mesoscale interactions and how heterogeneities profoundly affect the spatio-temporal evolution of thermo-electrochemical dynamics, establishing solid-solid point contacts as mechanistic pain points for consideration in improving solid-state battery cathode architectures.