Patent ID: 6285163
Filing Date: 2001-09-04
Classification: G01R

Abstract:
Means for estimating a state of charge of a battery, comprising a battery model for determining a pseudo-SOC (state of charge) as a temporary value representative of the SOC of the battery and estimating a voltage of the battery by considering the pseudo-SOC and a change in state of the battery, whereby a real SOC is estimated by correcting the pseudo-SOC so that the estimated voltage of the battery is equal to an actually measured voltage of the battery,wherein the battery model includes:pseudo-SOC estimating means for determining the pseudo-SOC from charging/discharging current of the battery,electromotive force estimating means for estimating the voltage of the battery in accordance with the pseudo-SOC output from the pseudo-SOC estimating means,voltage change estimating means for estimating a change in the voltage of the battery caused by internal resistance, anddynamic voltage change estimating means for estimating a change in the voltage of the battery based on a change in the charging/discharging current of the battery,wherein the voltage of the battery is estimated from the sum of output values of the electromotive force estimating means, the voltage change estimating means, and the dynamic voltage change estimating means.