摘要 |
<p>A backup battery charger charges a backup battery of a handheld electronic device. The handheld electronic device comprises a power supply unit and an electronic component. The power supply unit supplies a power to the electronic component. The backup battery charger is connected to the electronic component, such that the backup battery charger shares with the electronic component the power, uses the power as a charging power, and controllably determines via a control module whether to supply the charging power to the backup battery.</p> |