Mechanistic Origin and Role of Heterogeneities in Solid-State Batteries

Solid-state batteries (SSBs), consisting of a lithium metal anode and an inorganic solid electrolyte, promise to simultaneously improve the energy/power density and safety as compared to the conventional lithium-ion batteries. However, the complex nature of solid-solid interfaces in SSBs pose a wide range of challenges including the morphological instability of the metal anode, microstructure-driven kinetic and transport interactions in the cathode, and interphase formation. To address these limitations, gaining fundamental understanding of the myriad heterogeneities at scales, and their implication on the electrochemical-transport-mechanics interactions at such solid-solid interfaces is critical. In this presentation, we delineate the underlying role of heterogeneities on the failure onset, degradation, and electrochemical performance of solid-state batteries. The mechanistic interactions due to the spatio-temporal heterogeneity of the underlying electrochemical-thermal-mechanics coupling will be examined.