Computational screening and descriptors for the ion mobility in energy storage materials

Ion mobility in electrolytes and electrodes is a critical factor influencing the performance of batteries. Low ion mobility is, for example, one of the major factors reducing the range of battery-electric vehicles in winter. On the other hand, with respect to the ion mobility in battery cathode materials, there are scaling relations linking large insertion energies and thus high voltages with high migration barriers corresponding to low ion mobility. Consequently, a compromise has to be made between these two conflicting properties. In this opinion, we will address how computational screening and the identification of descriptors can accelerate the search for solid battery materials with improved ion migration properties, but we will also discuss how the scaling relations linking reaction and activation energies might be overcome.