I'm experiencing some strange behavior with my Droid battery. A couple of days ago I had it sitting out on the patio when it got dark. It got a bit cool after that, say between 50-55 degrees (I'm in Florida); when I went out to get it a couple of hours later it said that the battery was less than 5% and was going to shut off soon. I promptly connected it to the A/C charger and it instantly went to 60%. Since then however, it won't fully charge. It gets "stuck" at 90% and won't charge any further. If I can believe the icons it's continuously charging whenever connected to A/C, computer, or car (i.e. never says "charged" and the lightning bolt is always showing on the icon). I'm not sure if the battery has a problem, or if the calibration what is fully charged in the phone is at fault. As far as I can tell there isn't any way to do a battery calibration like is possible on some higher end laptop computers. I'm also not sure if having the charging circuit running constantly when the phone is connected to external power is going to cause some sort of additional problem. I haven't noticed a significant change in the runtime of the battery yet, but then I typically don't have it off the charger for more than a few hours at a time.