| 摘要 |
PROBLEM TO BE SOLVED: To exactly determine whether or not an engine can be started.SOLUTION: An apparatus for detecting a secondary battery state includes: a current detection means 12 for detecting a current value of an electric current passing through a secondary battery 14; an extremal value detection means for detecting a first extremal value of an electric current on the basis of a current value after energization of a starter motor is started and a rush current runs through the starter motor from a secondary battery; an inflection point detection means for detecting a first inflection point of an electric current on the basis of a variation per predetermined time of the current value after the rush current runs; and a calculation means for selecting an inflection point when the timing that an extremal value and an inflection point are detected is equal to or longer than a predetermined time, selecting either one of the extremal value and the inflection point to take the either one as a starting current in any other case, and calculating a starting voltage from the starting current, an internal resistance of the secondary battery and a pre-starting voltage that is a voltage of the secondary battery before the energization of the starter motor is started. |
