Battery pack, battery charger, and battery pack system

摘要

A battery pack includes: a plurality of rechargeable batteries (11a to 11n) connected in series or in parallel; a voltage detector (13) for detecting voltages of the respective batteries; a calculator (15) for calculating optimal charging current values based on the voltages of the respective batteries detected by the voltage detector so as to recharge the respective batteries; and a communicator (19) for transmitting the charging current values calculated by the calculator to a battery charger (3).