Patent attributes
A voltage monitoring device monitors voltage of each of battery cells connected in series to one another to configure an assembled battery. The device includes a capacitor circuit, a filter circuit, an input side connection switching unit, a potential difference detection unit, and an output side connection switching unit. The capacitor circuit includes a plurality of capacitors connected in series to one another. The filter circuit includes a plurality of resistors connected to an electrode terminal of each of the battery cells. The plurality of resistors are divided into a first resistor group and a second resistor group. The first resistor group is connected to a connection point between adjacent capacitors of the plurality of capacitors. The second resistor group is connected to an independent end of the plurality of capacitors. A resistance value of the first resistor group is smaller than a resistance value of the second resistor group.