A control device includes: a voltage control unit that sequentially switches a command voltage of a direct current-direct current converter between different predetermined measurement voltages to control the command voltage; an obtaining unit that obtains, for each of the measurement voltages, a first terminal voltage of a battery when constant current discharge is performed and a second terminal voltage of the battery when constant current charge is performed; and a correction unit that corrects an SOV-OCV characteristic curve indicating a relationship between the state of charge and an open circuit voltage of the battery, based on a comparison between the first terminal voltages newly obtained by the obtaining unit and the first terminal voltages immediately previously obtained by the obtaining unit and a comparison between the second terminal voltages newly obtained by the obtaining unit and the second terminal voltages immediately previously obtained by the obtaining unit.