The process which measures the polarization voltage presumption manner of charge and discharge electric variable presumption manner and the device and the accumulator of the accumulator, and the tupple data of terminal voltage of the aforementioned

摘要

An apparatus estimates charge/discharge electricity amount without being affected by current measurement error. Under specific selection conditions, a no-load voltage calculation part uses pairs of data consisting of current data I(n) and voltage data V(n) corresponding to the current data to calculate a no-load voltage Vsep as the voltage intercept at a current of zero in a straight-line approximation obtained by statistical processing such as regression analysis using a least squares method. If specific current conditions exist for a certain amount of time, an open circuit voltage calculation part calculates the terminal voltage of the secondary battery as the open circuit voltage Voc. An estimated charge/discharge electricity amount calculation part uses a preset change-in-voltage adjustment constant Vbc/adjustment coefficient Kb, change-in-electromotive-force constant Keq and polarization voltage generation constant Kpol to calculate the estimated charge/discharge electricity amount Qe as a function of the change Vb in the no-load or open circuit voltage over a predetermined period of time.