UNINTERRUPTIBLE POWER SUPPLY AND BATTERY ACTIVATION OPERATIOND METHOD THEREOF

An uninterruptible power supply comprising a first switch unit, a charging circuit, a first voltage conversion circuit, a second voltage conversion circuit, a second switch unit and a control circuit is provided. When the uninterruptible power supply performs a battery activation operation, the control circuit controls the first switch unit to provide the AC power received by the uninterruptible power supply to a terminal of a bypass path, controls the first switch unit to provide the output of a battery to the first voltage conversion circuit, controls the second switch unit to electrically couple the output terminal of the uninterruptible power supply to the other terminal of the bypass path, controls the charging circuit to stop charging the battery, and controls the first voltage conversion circuit to perform a DC-DC conversion operation. In addition, a corresponding battery activation operation method is also provided.