I'm succesfull running an Arduino on a breadboard, powered with 3 AAA recharchable batteries. After a couple of weeks, the Arduino stopped running (earlier than I expected since the sketch is sleeping in low power mode most of the time).
When I measured the voltage of the 3 batteries I noticed something strange: - 1st battery: 1.2v - 2nd battery: 0.9v - 3rd battery: 0.2v
Anybody has an idea what could cause 1 battery depleting much earlier than te rest? They were connected in series and all of them were completely charched in the beginning.