A full charge capacity value correction circuit includes: a current detection portion which detects a current value in a secondary battery; a voltage detection portion which detects a terminal voltage value of the secondary battery; a capacity storage portion which stores a full charge capacity value of the secondary battery; a remaining quantity calculation portion which calculates a remaining charging quantity in the secondary battery a remaining quantity estimation portion which estimates a remaining quantity of the secondary battery and a full charge capacity value correction portion which, when an estimated remaining quantity becomes equal to a reference value set in advance, adds a difference electrical quantity, to the full charge capacity value stored in the capacity storage portion, or subtracts the difference electrical quantity from the full charge capacity value stored in the capacity storage portion based on an estimated remaining quantity and an accumulated remaining quantity.