Grain Boundaries in Ceramic Solid-State Lithium Metal Batteries: A Review

Abstract

It is now widely accepted that grain boundaries play a critical role in the performance and reliability of solid-state batteries with lithium metal anodes. Understanding and controlling grain boundaries is essential for enabling safe, high-rate operation of solid-state batteries. This review explores the multifaceted influence of grain boundaries in ceramic solid electrolytes and metal anodes, including their impact on ionic and electronic transport, dendrite and void formation, connecting them to the failure mechanisms. We discuss the formation and structure of space charge layers at grain boundaries, their role in modulating local defect chemistry, and the conditions under which grain boundaries may serve as fast-ion pathways or as vulnerable sites for failure. We highlight key differences in the grain boundaries of different classes of solid electrolytes and advances in modeling, experimental characterization, and processing techniques to understand the complexity and engineer grain boundaries in solid electrolytes. Finally, we outline key open questions and opportunities for grain boundary engineering to stimulate further progress in the field.

67 pages, 22 figures

References in corpus (11)

• Stability of Electrodeposition at Solid-Solid Interfaces and Implications for Metal Anodes
• Universal Chemomechanical Design Rules for Solid-Ion Conductors to Prevent Dendrite Formation in Lithium Metal Batteries
• Stacking Faults Assist Lithium-Ion Conduction in a Halide-Based Superionic Conductor
• First-principles prediction of potentials and space-charge layers in all-solid-state batteries
• Effects of Grain Boundaries and Surfaces on Electronic and Mechanical Properties of Solid Electrolytes
• Role of anisotropy in determining stability of electrodeposition at solid-solid interfaces
• Constriction and contact impedance of ceramic solid electrolytes
• Chemomechanics: friend or foe of the "AND problem" of solid-state batteries?
• Heterogeneity in Point Defect Distribution and Mobility in Solid Ion Conductors
• Modulation of Point Defect Properties Near Surfaces in Metal Halide Perovskites
• A unified and consistent electrical double layer model for treatment of core and space charge layer in solid electrolytes