DEVICE FOR DETERMINING STATE OF LEAD-ACID BATTERY AND METHOD FOR DETERMINING STATE OF VEHICLE AND LEAD-ACID BATTERY

摘要

PROBLEM TO BE SOLVED: To appropriately calculate the remaining capacity of a lead-acid battery irrespective of the nominal capacity of the lead-acid battery.SOLUTION: A state determination device 10 for a lead-acid battery 2 comprises: a voltage detection unit 102 for detecting the terminal voltage of the lead-acid battery; a current detection unit 103 for detecting a charge current and discharge current flowing in the lead-acid battery; a first acquisition unit 106 for acquiring the open-circuit voltage of the lead-acid battery from the terminal voltage detected by the voltage detection unit; a first arithmetic unit 105 for calculating the charge/discharge capacities of the lead-acid battery by using the charge current and discharge current detected by the current detection unit; a first storage unit 101 for storing a preset maximum voltage value and minimum voltage value of the open-circuit voltage of the lead-acid battery; and a second arithmetic unit 108 for calculating the remaining capacity of the lead-acid battery by using a plurality of open-circuit voltages of the lead-acid battery acquired by the first acquisition unit, the charge/discharge capacities of the lead-acid battery at a time when each of the plurality of open-circuit voltages of the lead-acid battery is acquired by the first acquisition unit, and the maximum voltage value and minimum voltage value.