STORAGE BATTERY INSPECTION DEVICE AND STORAGE BATTERY INSPECTION METHOD

A storage battery inspection device includes: an energy storage control circuit that applies an alternating current to a storage battery; a magnetic sensor that senses a magnetic field component outside the storage battery and outputs a magnetic sensor signal indicating the sensed component; a canceling coil that generates a magnetic field component based on an input current to cancel out a magnetic field component generated by magnetization of a magnetic material in the storage battery; a feedback circuit that obtains, from the magnetic sensor signal, a low-frequency signal indicating a magnetic field component having a lower frequency than the alternating current, and applies the input current to the canceling coil based on the low-frequency signal; and a detection circuit that obtains, from the magnetic sensor signal, a detection signal indicating a magnetic field component having the same frequency as the alternating current.