from what read this problem could be from a damaged usb flex. i have this problem. due to this i cant even shut down the tablet...cause it turns on screen to show charging process. by disconnecting battery and reconnecting it doesnt show charging...but as soon as i plug charging cable it says charging but doesnt charge for $@$*. unplugging it and it stays on charging status. for the time being i kept the nexus battery cable disconnected aside trying to figure out a solution. hopefully someone who fixed it pops up. let me know if you fixed it...ok :p