Modeling and Characterization of Thin-Film Solid–Solid Interfaces in Lithium Solid-State Batteries

This chapter describes the development and application of model thin-film electrodes for advanced all-solid-state lithium battery technologies. Employing 001-oriented Li2MnO3 electrodes and a novel vacuum-type spectroelectrochemical cell, this study focused on analyzing the solid–solid interfacial reactions. The Li2MnO3 electrodes exhibited significant capacity enhancement and superior cycle stability in solid configurations compared with their liquid counterparts. Through in situ X-ray diffraction, a gradual phase transition contributing to the high discharge capacity was identified. This study sets a new benchmark for material and/or interfacial design and performance optimization in solid-state batteries.