bartveld

Yesterday, after spending the night on the charger, my TyTN II's battery went down from 100 to 25% in about half an hour. After that, it continued downward, even when on the charger and the icon showing it charging.
This morning, after another night charging, the battery is on 0% and on turning the phone on it starts an immediate resetloop.
Is the battery gone? Or should it be recalibrated? How do you do that? I've already tried soft resets and taking out the battery for a while. Would a hard reset help? But when I restore my system after that, would I also restore (faulty) calibration information?