Lead storage battery deterioration determination device and lead storage battery deterioration determination method

摘要

PROBLEM TO BE SOLVED: To determine deterioration of lead storage batteries connected in parallel with a secondary battery other than the lead storage battery.SOLUTION: A deterioration determination device of a lead storage battery includes: a power supply part including lead storage batteries connected in parallel with each other and a second battery other than the lead storage batteries; a current determination part for determining whether or not an inrush current flowing to the lead storage batteries at a start of the engine is below an upper limit of the current detectable by the current detection part; a resistance calculation part for dividing a starting voltage by the inrush current and calculating an inner resistance of the lead storage battery; and a deterioration determination part for determining that the lead storage battery is deteriorated when the inner resistance of the lead storage battery is higher than a resistance threshold value by comparing the inner resistance of the lead storage battery with the resistance threshold value. The secondary battery of the lead storage battery has characteristics that an increase ratio of the inner resistance of the lead storage battery is larger than the increase ratio of the inner resistance of the secondary battery.SELECTED DRAWING: Figure 1