| 摘要 |
PROBLEM TO BE SOLVED: To discontinue charging after a predetermined elapse of time of an overcharged state and start charging again after the overcharged state is dissolved, by a method wherein a thermal operation means, which is made to operate by the heat of a resistor in the overcharged state, and can be used repeatedly, is provided. SOLUTION: At the time of charging, the voltages of lithium ion batteries 1 and 2 are monitored by a voltage detecting means 5. If the voltage of one of the batteries exceeds a predetermined voltage, it is judged that the battery is in an overcharged state and a current is applied to a resistor 7 by a resistor current supply means 6. The resistor 7 is thermally coupled with a bimetal thermal operation means 8 provided in the current supply circuit of a charging current and, 10-30 minutes after the start of the current supply to the thermal operation means 8, a contact between the fixed contactor 9 and the movable contactor 10 of the thermal operation means 8 is opened and the charging is discontinued. As the thermal operation means 8 is restored by the drop of a temperature after the overcharged state is dissolved, the charging operation can be started again. |
