BATTERY DETERIORATION DETERMINATION DEVICE, HYBRID VEHICLE, AND BATTERY DETERIORATION DETERMINATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a battery internal state estimation device capable of accurately estimating an internal state of a battery by reflecting the temperature distribution of each cell constituting the battery while suppressing increase in computation load.SOLUTION: A battery ECU (28) estimates, on the basis of an equivalent circuit model, a temperature distribution inside a battery (11) in a case where the battery (11) after being used for a predetermined period is deteriorated normally. A vehicle ECU (20) detects a temperature distribution inside the battery (11) which has been used for the predetermined period from an actual temperature of each cell (11a) detected by a battery temperature sensor (31). It is then determined whether the deterioration state of the battery (11) is normal deterioration or not by comparing the estimated temperature distribution with the actual temperature distribution.SELECTED DRAWING: Figure 4