Originally Posted by Bookworm_Girl
Did you have Wi-Fi on? Sometimes if there is an internet failure overnight or intermittent Wi-Fi it can drain the battery fast because it's continuously searching for a good connection.
This happened to me, though at the time I was puzzled at the rapid battery drain. It was to the point where it was locked on the screen saver. Took five minutes of charging to get the message that battery too low to power on.