Elucidating Ionic Mobility and Structure Relationships to Enable Energy Storage

Understanding the intricate relationship between atomic structure and ion motion is crucial for optimizing the performance of battery materials. This thesis aims to explore this theme through a series of comprehensive studies. Investigations are performed via in situ XRD into the synthesis pathways and challenges for antiperovskite materials, shedding light on how specific structural arrangements and the formation of solid solutions influence ionic mobility. The potential of multivalent spinel oxides, particularly magnesium-based materials, is examined for rechargeable battery cathodes. Through structural modifications such as metal doping and cation inversion, the critical role of local structural features in determining bulk properties is revealed. Additionally, we evaluate the significance of disorder within solid electrolytes, with a focus on the paddlewheel effect observed in the ion transport mechanisms. Using experimental techniques such as neutron and x-ray diffraction and pair distribution function, and computational methods like reverse Monte Carlo profiling and AIMD, this research explores disorder within polyanion groups and sodium cation transport pathways. Our findings shed light on the interplay between static and dynamic disorder, offering valuable insights into the mechanisms governing ion dynamics and solid-state electrolyte functionality. Overall, this thesis underscores the importance of understanding atomic structure for elucidating ion motion in battery materials, providing crucial insights for the development of more efficient energy storage systems.