Ion mobility is a critical performance parameter in batteries. Low ion mobilities lead to small charging and discharging rates and also dissipation losses which reduce both the power and the energy density of batteries. Hence there is a quest for battery materials with improved ion migration properties . First of all it is important to note that there is a fundamental difference between the ion mobility in liquids and in solid materials. Whereas migration in liquids is in general a continuous process that can be driven by random processes or by gradients in some relevant property such as gradient or potential , migration in solids corresponds to hopping between local energy minimum sites .