Disclosed is a bag with a built in charger for portable electronic devices. The bag includes an interior compartment that is disposed between an interior lining and an exterior of the bag. The interior compartment is adapted to hold a battery unit, which is removably connected to a charging cable and a retractable power cable. The charging cable can be connected to the battery unit via a USB connection, and is adapted to connect to a portable electronic device via a mobile device connection. The retractable power cable can be extended out of the interior compartment through a side opening, and can connect to an electrical outlet via a plug. An electrical connection between the electrical outlet and the plug supplies energy to the battery unit. The energy stored in the battery unit can be used to charge the portable electronic device when an electrical outlet is not readily accessible.