Secondary battery charging device, method of charging in secondary battery charging device, photovoltaic generator, method of power generation in photovoltaic generator, photovoltaic-charged secondary battery system, electronic device, and electrical vehicle

摘要

A battery charging device includes a battery pack including a plurality of battery cells connected in series, and a control unit. The control unit is configured to change a series connection of the battery cells in response to a variation in output voltage of a solar battery.