EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Stable and fast ionic conductors for magnesium cathode materials have the prospect of enabling high energy density batteries beyond current Lithium-ion technologies. So far, only a few candidate materials have been identified leading to data only being scarcely available. One of the reasons is the long time it takes to quantify ion conductivity computationally. This limits the development of simple descriptors that can predict ion conductivity.

Here, we present a systematic screening study, in the framework of Density Functional Theory, including the estimation of the diffusion barrier for 16 materials through employing Nudged Elastic Band (NEB) calculations. By introducing a path finder tool based on the idea of Voronoi tesselations, we show that an estimate of the transition state configuration can be extracted prior to running NEB-calculations. Using geometrical descriptors in combination with a Principal Component Analysis it is possible to further subdivide the NEB-paths into diffusion topology groups. We show that this approach also extends to materials which are not part of the screening study, making it a viable approach to more efficiently explore crystal structures with distinguishable diffusion characteristics.