Battery-powering the Beagle Board
I'm now running the Beagle Board on battery power.
I had gotten myself two battery power supplies before starting this project, both of which looked promising in terms of being able to battery-power the Beagle Board. One is a verified peripheral for the Beagle Board, a 2xAA battery cellphone charger, the other one is this Li-Ion battery pack from a UK company, which I decided to get because at the very least I would be able to use it with my Microtrack 24/96 portable audio recorder. Well, it turned out the first device - in spite of being a verified Beagle Board peripheral - does not comply with the board's specifications very well. Its voltage fluctuates quite wildly between 4.7 and 6.0 V, so I have not dared yet to try that with the board (which is speced for a maximum of 5.2 V). The Li-Ion battery pack on the other hand outputs a quite stable voltage - at 80% of the specified value (4.0 rather than 5.0 V). However, I just tried it with the Beagle Board, and it seems to be enough to power the board reliably; at least when using the USB OTG port (rather than the actual power plug) to plug the battery pack into. Good news!