All-solid-state batteries (ASSBs) have emerged as a promising technology to address the current risks and limitations of conventional liquid electrolyte-based Li (and potentially Na) ion batteries. However, achieving ASSBs with competitive cell performance remains challenging. Despite notable progress in recent years, several issues persist at the material, electrode, and cell levels limits the performance. These include insufficient interfacial contact and electrochemical instability between the cathode active material (CAM) and the solid electrolyte (SE) within composite cathodes (CCs), as well as residual porosity from processing and chemo-mechanical ageing caused by coupled electrode volume changes during cycling. Furthermore, inadequate ionic and electronic transport pathways continue to hinder performance. To address these challenges and to deepen our understanding of performance-limiting mechanisms and processability, it is essential to correlate microstructural and electrochemical properties across multiple length scales. In particular, the relationship between local cathode microstructural evolution and the macroscopic volumetric response of the full cell stack, encompassing contributions from all active components, remains insufficiently understood. Multi-scale imaging workflow and operando FIB-SEM analyses offer valuable insights into these interdependencies.  In my talk, I present an inert-gas-compatible workflow that combines high-resolution X-ray microscopy (XRM) with correlative femtosecond-laser/FIB sample preparation and FIB-SEM tomography. Moreover, operando FIB-SEM studies of cathodes in sulfidic Li-ion ASSBs are shown to reveal microstructural evolution during cycling. This synergistic workflow contributes to a more comprehensive understanding of ASSB cathode microstructure across different length scales and its influence on the electrochemical behavior of complete cells and individual components.

Short Biography of the Speaker:

Dr. Kaya is a junior research group leader for all-solid-state batteries (ASSBs) at the “Institute for Materials Research (IMFAA)” at Aalen University of Applied Sciences in Germany. She received her B.Sc. in the field of Materials Science and Engineering in 2007 and M.Sc. degree in the field of Nanotechnology in 2010 at Eskisehir Technical University (Anadolu University), where she studied scanning/transmission electron microscopy (S/TEM) and electron energy loss spectroscopy techniques. She completed her PhD in 2017 on bulk and thin-film thermoelectric materials, ionic conductivity, and defect chemistry at the Max Planck Institute for Solid State Research (MPI-FKF); after a brief postdoctoral period there, she joined IMFAA in Aalen. Dr. Kaya has conducted research on microstructure-property relationships in various energy conversion and energy storage materials for many years, and she and her team are currently particularly interested in microstructural effects and their influence on the properties of Li-&Na-ASSBs at the electrode and cell level.