Patent ID: 7489112

Claim:
A voltage detecting device for an on-vehicle high-voltage battery in which a plurality of secondary batteries are connected in series, the on-vehicle high-voltage battery being divided into a plurality of blocks each including at least one secondary battery, the voltage detecting device comprising: a plurality of voltage detectors each assigned to a respective individual block for detecting a voltage of each secondary battery included in the respective block; and a controller for controlling the plurality of voltage detectors; wherein a common secondary battery is selected from a plurality of the secondary batteries, a voltage of the common secondary battery being measurable by a first one of the voltage detectors which is assigned to the respective block containing the common secondary battery, and also being measurable by a second one of the voltage detectors which is assigned to a different one of the blocks that does not contain the common secondary battery; and wherein the controller causes both of the first and second voltage detectors to measure the voltage of the common secondary battery, computes a detection error between the two voltage detectors on the basis of the detected voltage values of the common secondary battery, and makes corrections in voltage values detected by the two voltage detectors on the basis of the computed detection error.