A movie of lithium ions quickly moving along 'easy pathways' in intermediate configurations of LTO. Imagine the LTO lattice as a racecar obstacle course that the lithium ions have to navigate around. In its original phase (Li4Ti5O12) and the end phase it transforms into to accommodate lithium ions (Li7Ti5O12), LTO has atomic configurations in which many obstacles are in the way. Thus, lithium ions must travel slowly through the obstacle course. But in intermediate configurations of LTO (such as the Li5+xTi5O12 shown in the movie), local distortions in the arrangement of atoms surrounding lithium occur along the boundary of these two phases. These distortions slightly shovel the obstacles out of the way, giving rise to a 'fast lane' for lithium ions to speed through.