Scanning probe methods have long been employed to conduct local electrochemistry. However, connecting these measurements to macroscopic electrochemical performance of an electrode can be challenging. Workers have recently begun exploring strain-based methods sensitive to local defect concentrations in materials. These include electrochemical strain microscopy (ESM) and more recently scanning thermo-ionic microscopy (STIM). The basis for these techniques will be discussed, with examples involving Li battery materials and the study of grain boundaries in rare-earth doped ceria. Also discussed will be the possible application of these techniques as local witnesses of defect concentrations in complex electrode structures during impedance or other transient measurements.