Electrolytic effects, crystal coloration, and charge storage observed when an electric field is applied to single crystals of calcium orthovanadate at temperatures above 700 °C are shown to be associated with oxygen migration and the creation of V4+ centers in the crystal. The oxygen transport number is shown to be constant at 0.9 over the temperature range 650°–900°C with an activation energy for predominantly ionic conduction of 1.05 ± 0.05 eV. The amount of recoverable charge stored in the crystal depends on the sample used and also on the charging current, but is about 15% for an average crystal with a charging current density of several milliamperes/square centimeter. The open‐circuit voltage is of the order of several volts. Deterioration of the bulk material during electrolysis and barrier effects appear to be the major limitation on the use of the material as a charge storage medium.