BATTERY MEASUREMENT DEVICE

A battery measurement device that measures a state of a secondary battery includes: a signal control section that causes an alternating-current signal to be outputted from the secondary battery or inputs an alternating-current signal to the secondary battery; a current measurement section that measures the alternating-current signal; a response signal measurement section that measures a response signal of the secondary battery responsive to the alternating-current signal; and a calculation section that calculates information regarding a complex impedance of the secondary battery based on measurement results of the alternating-current signal measured by the current measurement section and the response signal measured by the response signal measurement section. The arithmetic section calculates the information regarding the complex impedance after waiting for the measurement result of the alternating-current signal to reach a steady state after start of the input/output of the alternating-current signal by the signal control section and outputs a calculation result.