Efficient electrochemical energy storage and conversion require high performance electrodes, electrolyte or catalyst materials. In this contribution we discuss the simulation-based effort made by Institute of Energy and Climate Research at Forschungszentrum Jülich (IEK-13) and partner institutions aimed at improvement of computational methodologies and providing molecular level understanding of energy materials. We focus on discussing correct computation of electronic structure, oxidation states and related redox reactions, phase transformation in doped oxides and challenges in computation of surface chemical reactions on oxides and metal surfaces in presence of electrolyte. Particularly, in the scope of this contribution we present new simulated data on Ni/Co and Am/U-bearing oxides, and Pb, Au and Ag metal surface materials. The computed results are combined with the available experimental data for thoughtful analysis of the computational methods performance.