摘要 |
PROBLEM TO BE SOLVED: To prevent power consumption only of a specific battery pack, out of a plurality of battery packs connected in series, from increasing.SOLUTION: A battery pack module which can be connected in series with other battery pack module, including a plurality of battery cells connected in series, includes a battery pack, a first power supply, and a changeover section. The first power supply supplies power of the battery pack as a first drive force. When the other battery pack module and the battery pack module are connected electrically in series, the second power supply supplies the power of the other battery pack module and the battery pack module as a second drive force. Until the other battery pack module and the battery pack module are connected electrically in series, the changeover section supplies the first drive force to a driven section, and supplies the second drive force to a driven section after the other battery pack module and the battery pack module are connected electrically in series. |