 We use time-domain electrostatic force spectroscopy (TD-EFS) for characterizing the ion dynamics in solid electrolytes on a nanoscopic level. For partially crystallized glass ceramics we are able to distinguish between dynamic processes in the glassy phase, in crystallites, and at interfaces. Nanoscopic polarization spots can be created and directly visualized, and their time evolution can be studied. By applying grid-type spectroscopic measurements, maps of the local relaxation strength can be obtained, giving information about the spatial distribution of the glassy and crystalline phases.