Abstract: A battery-charging adapter for a hand-held personal digital assistant (PDA) of the type that is placed in a data cradle. The adapter includes a battery pack that replaces the batteries in the PDA and has a recharging interface, a door that replaces the door of the PDA's battery compartment and permits access to the battery pack's recharging interface when the door is closed, and a surface which is attachable to the data cradle and has a recharging interface and recharging circuitry which is coupled to the recharging interface and a power supply. When the adapter surface is attached to the data cradle and the PDA is in the cradle, the battery pack's recharging interface is coupled to the adapter's recharging interface, permitting the batteries in the PDA to be recharged while the PDA is in the cradle.