The battery indicator in my D5100 has 3 'bars' but fails to operate shortly after reaching 2 bars. My experience is; Three bars indicates battery is good Two bars indicates battery is going to fail imminently One bar doesn't figure at all! This weekends experience. A check on the battery life shows 2 bars so I don't bother recharging for the next day. Next day take a couple of shots and the camera fails to focus and the battery indicator flashes. Remove the battery, heat up in my hand and replace. Two bars showing and I manage another 15 shots before total failure. Do I have a faulty battery? Is there any way to check this?