Patent ID: 7619389

Claim:
A charge control device comprising: a charge circuit for supplying a charging voltage (Vc) or a charging current (Ic) to a secondary battery used for driving an appliance; charged level setting means for switching a charged mode between a fully charged mode in which a fully charged state is a targeted charged state and a low charged mode in which a charged state whose charging rate is decreased by a predetermined percentage from that of the fully charged state is a targeted charged state; detection means for detecting a charged level of the secondary battery; discharge means for discharging the secondary battery; control means for operating the charge circuit while a charged level detected by the detection means is lower than a targeted charged state in the charged mode, which is currently selected by the charged level setting means, and operating the discharge means while a charged level detected by the detection means is higher than a targeted charged state in the charged mode, which is currently selected by the charged level setting means; and a storage device for storing a fully charged capacity of the secondary battery in the fully charged mode, and for storing a fully charged capacity of the secondary battery in the low charged mode, wherein in the low charged mode, a remaining capacity of the secondary battery is indicated in accordance with the following equation: RSOC(%)=RC/(FCC/CV)*100, wherein RSOC is the remaining capacity of the secondary battery, RC is a current charge capacity of the secondary battery, FCC is the fully charged capacity of the secondary battery in the low charged mode, and CV is a conversion factor, and wherein the fully charged mode is a first constant-voltage charged mode in which the secondary battery is charged at a first voltage, and the low charged mode is a second constant-voltage charged mode in which the secondary battery is charged at a second voltage which is lower than the first voltage.