This project aims at developing computational materials design approaches to speed up the design of electrolyte materials compatible with high energy density electrodes, targeting the next-generation of electric vehicle’s batteries. The strategy is to design novel polymer electrolyte hosts and target stable electrochemical interfaces to. The specific goals are: (i) To achieve fundamental understanding on the underlying mechanisms of the reactivity on the lithium metal/electrolyte or high voltage cathode/electrolyte interfaces, unveiling the atomic-level properties that govern the electrochemical stability. (ii) To develop a novel high-throughput computational materials design (HCMD) approach, incorporating ionic conductivity in the materials screening step to search for highly conductive polymer electrolytes. Li-ion batteries have provided a lot of advancement to the mobile devices since its first commercialization in 1990. Now, new Li-battery concepts are emerging with the potential to surpass the present energy storage capabilities (250 Wh/Kg and 800 Wh/l) for electric vehicles, not least realized through different solid-state battery concepts employing Li-metal electrodes. The popularization of such technology is a route to enable a sustainable world growth with reduced impact on the environment. However, there are many challenges facing these technologies, and in particular they still depend on the development of stable Li-metal anode and high-voltage cathodes for successful commercialization. In this project, we will investigate the electronic structure, electrochemical properties and ionic conductivity mechanism in some target solid polymer electrolyte materials and at relevant electrode interfaces, from density functional theory (DFT) and molecular dynamics (MD). The ultimate goal is to establish the compostion-structure-properties relationships. Moreover, we will build a wide library of solid-state electrolyte candidates (including existing and hypothetical compounds) adding key properties that will be calculated from accurate DFT. We aim at exploring surface passivation of the electrodes, decomposition products, and transport properties in the electrolyte and formed interphases. The project involves work associated with both a granted application in 2020 from the Swedish Energy Agency and one from Horizon Europe (PSIONIC) in 2022.