To easily and accurately detect the characteristics of a secondary battery of a hybrid vehicle.
MG44 is controlled from an MG control processing part 101 of CPU40 by way of a motor controller 74, and by changing the frequency of a state sensing current flowing in the secondary battery 10, the current and voltage of the cell 10 are detected. Based on a plurality of detected results, an impedance is calculated with an impedance calculating part 100. Remaining quantity is calculated with a remaining quantity operator 102, from the obtained impedance and the cell characteristics contained in a memory 80. Furthermore, an integrated current during impedance measurement is added to the remaining quantity, in a remaining quantity variation correction part 104 for correction and weighting factor is determined, based on a standard deviation from the correction value and the remaining quantity, in order to average with a weighting average part 106. Then, by using the remaining quantity calculation, lifetime calculation and lifetime correction calculation are conducted, to average with the weight similarly to the remaining quantity.
MIYAZAKI HIDEKI
EMORI AKIHIKO
HIRASAWA IMAKICHI
SHIN KOBE ELECTRIC MACHINERY
Kyosuke Tanaka
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