A battery charging system of an electronic device includes: a battery having a first nominal voltage and including: battery cells each having a second nominal voltage that is less than the first nominal voltage; and electrical connectors that electrically connect ones of the battery cells to provide the battery with the first nominal voltage; a first charge port configured to electrically connect to a first type of connector; a charging module configured to: receive power via the first charge port; and when a voltage of the received power is less than the first nominal voltage at least one of: charge ones of the battery cells individually; and charge groups of two or more of the battery cells.