Hi.
I had a problem with my battery this week, it happens only one time, during skiing (maybe due to cold weather, about -4°c?) when I tried to make a video. Red icon, and telling impossible to make a video due to low level batery. When I took my N9 out of the pocket, few hours after, to charge it, battery was ok again!!!
I used the phone with lower temperature (-15°C) without such trouble.
Any idea?