BATTERY MONITORING DEVICE

A current application unit includes a load element, a switching element, and a shunt resistor connected in series between both terminals of an assembled battery, and a drive control unit of the switching element to apply an alternating current having a predetermined frequency to the assembled battery. The drive control unit includes: a PWM modulator for generating a drive signal; a PDM modulator for generating the drive signal; and a switching unit for switching between a first drive state for driving the switching element by the drive signal generated by the PWM modulator and a second drive state for driving the switching element by the drive signal generated by the PDM modulator.