Build an aa charger and nicd powered as reported by Stefanv. This project, which involves charging nickelcadmium nickelhydride cells in pairs using the power of the port, solves the problem.
Battery charger conforming to Wikipedia. Battery charger, device used in the secondary rechargeable battery in electric current. Charge how long of time, when the charge instance depends on type charged battery.
Thermoelectric usb charger in line with Instructables. This strange device generates from the temperature source. Using the effect, able enough electricity to.