DETERIORATED CAPACITY ESTIMATING DEVICE AND DETERIORATED CAPACITY ESTIMATING METHOD FOR ELECTRICITY STORAGE ELEMENTS, AND ELECTRICITY STORAGE SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a deteriorated capacity estimating device that can accurately estimate the discharge capacity of electricity storage elements at a prescribed time of deterioration.SOLUTION: A deteriorated capacity estimating device 100 for estimating the deteriorated capacity, which is the discharge capacity at a prescribed time of deterioration, of an electricity storage element 200 comprises a relational expression acquiring unit 110, that acquires a first relational expression which, supposing the discharge at the time of discharging the electricity storage element 200 with a prescribed first current to be the storage capacity and the discharge at the time of discharging the electricity storage element 200 with a second current lower than the first current to be the equilibrium-based capacity, represents the initial capacity of the electricity storage element 200, an equilibrium-based capacity drop, which is the balance of subtraction of the equilibrium-based capacity from the initial capacity, a velocity-based capacity drop, which is the balance of subtraction of the storage capacity from the equilibrium-based capacity, and the value of the DC resistance or the AC resistance of the electricity storage element 200, and a deteriorated capacity estimating unit 120 that estimates the deteriorated capacity, which is the storage capacity at the time of deterioration.