My Nook had virtually the same symptoms as azazel1024's:
- The battery will show (e.g.) 100%, and when you check a minute later it will show 34%, and then jump back to 90% (or some other value).
- The battery shows 90% and 100% but suddenly the Nooks turns off, saying it has no battery charge.
- Even after charging overnight it sometimes says it has no power.
- Sometimes when it says it has no power and turns off, you can connect it to the charger for a few seconds, unplug it and it will boot up and say it has plenty of battery.
Things tried, none helped:
- Charged it full, tried to drain the battery by using it, charge again.
- Factory reset
- Software updates: tried 1.0.1(?), 1.1.0, or 1.1.1 and 1.1.2.
After fighting with these problems for several weeks, I concluded that the battery or battery sensor is defective and got a replacement. I called B&N to get an RMA and got a replacement in store. My Nook was refurbished so I got a refurished one (with a charger). This one seems to be working fine so far...