You should check if you have 4G enabled. There is a bug few months ago that the log is constantly written and taking up internal storage and possibly the fact that 4G is so limited it is constantly failing to find a connection and attempting to reconnect....
Still getting a glitch with the battery usage. I'll have 60 percent and if I reboot it will then say I'm at 30 percent. Stock battery BTW. Edit..... I then reboot once more and I'm down to 17 percent. Reboot once more but this time into recovery and 4ext says 17 percent as well