Patent ID: 6967466

Claim:
A method for determining the amount of charge which can be drawn from a storage battery comprising: determining a battery voltage profile and a battery current profile over at least one time interval; smoothing the battery voltage profile and the battery current profile using at least two different smoothing measures; determining voltage differences between the battery voltage profile smoothed using a second smoothing measure and the battery voltage profile smoothed using a third smoothing measure, with the third smoothing measure producing greater smoothing than the second smoothing measure; determining current differences between the battery current profile smoothed using a second smoothing measure and the battery current profile smoothed using a third smoothing measure, with the third smoothing measure producing greater smoothing than the second smoothing measure; calculating characteristic values from quotients of the voltage differences and the current differences; utilizing the characteristic values for a time interval to determine an interval characteristic value; and determining of the amount of charge which can be drawn from the storage battery from at least one interval characteristic value for at least one time interval.