CIRCUIT FOR CHARGING, EMERGENCY LIGHTING DEVICE, AND LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To make judgment properly about the life of a battery when it is charged, to attain power saving and life prolongation. SOLUTION: An arithmetic operation control unit 16 turns a switch 17 of DC power on/off from a converter circuit 15 so as to intermittently charge a battery 13. The operation control unit 16 obtains difference voltage between the battery voltage when auxiliary charge is started in the case of intermittent charge and the battery voltage when the auxiliary charge is ended. When the internal resistance value of the battery 13 obtained by dividing the difference voltage by the charge current obtains a prescribed value or more, a life of the battery is judged. When the life of the battery is judged, an output apparatus 22 informs a user of the result of judgement. COPYRIGHT: (C)2005,JPO&NCIPI