Patent ID: 6252377
Filing Date: 2001-06-26
Classification: B60L,G01R,H02J,Y02T

Abstract:
An apparatus for detecting a remaining charge in a battery, comprising:a current detector for detecting an output electric current from and a regenerative electric current to said battery;a voltage detector for detecting a voltage output from said battery;a low-pass filter for filtering a plurality of detected current values and a plurality of detected voltage values;a time constant changer for changing a time constant of said low-pass filter;an integrator for calculating the remaining charge of said battery by integrating the plurality of detected current values detected by said current detector;a remaining charge detecting map for calculating a threshold voltage value corresponding to a specified value of the remaining charge, based on a filtered electric current value filtered by said low-pass filter;a comparator for comparing the threshold voltage value, calculated by said remaining charge detecting map, with a filtered voltage value filtered by said low-pass filter; anda resetter for resetting the remaining charge to said specified value of the remaining charge when the filtered voltage value exceeds said threshold voltage value.