PORTABLE RECHARGEABLE POWER SUPPLY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a portable rechargeable power supply device capable of preventing an overcharge by a simple configuration.SOLUTION: A portable rechargeable power supply device is provided with two input-output common terminals 31 for performing charging of a lithium ion battery pack 10 and supply of power from the battery pack 10 to the exterior. In addition, the portable rechargeable power supply device is provided with an overcharge prevention part 38. This overcharge prevention part 38 comprises: voltage dividing means for dividing a voltage applied to the input-output common terminals 31; cutoff signal generation means for determining whether or not the voltage applied to the input-output common terminals 31 at the charging of the battery pack 10 is larger than an upper limit voltage at the charging of the battery pack 10 by using the divided voltage, and generating a cutoff signal when it is determined that the voltage is larger than the upper limit voltage at the charging; and cutoff means for cutting off the charging of the battery pack 10 when receiving the cutoff signal from the cutoff signal generation means.