Progress in dynamical mean field-based electronic structure methods over the last years has provided us with precious tools allowing for a microscopic understanding of electronic mechanisms at work in correlated materials, including functional materials. In this talk, we will focus on layered transition metal sulphides studied for battery applications. Analysing the electronic structure, energetics and intercalation voltage, we find that Hund’s exchange coupling plays a crucial role for the electrochemistry of these compounds. We identify the battery charging process as a transition from a high-spin Mott insulator to a low-spin correlated metal. We argue that a deeper understanding of the microscopic mechanisms at work in such materials might contribute to paving the way to better battery materials in the future.
J.-H. Sim, D. D. Sarma, J.-M. Tarascon, S. Biermann, arxiv 2305.08526