Thanks Meter 298
Join Date: Jun 2006
Location: Southern California
Have the screen off.
Put it in the dock, phone will turn on, beep, launch the clock app and start charging.
Press the home button to go back to home screen, again make sure the battery icon shows charging.
Now leave it and the screen will turn off and should charge.
If you just leave the clock app on the phone doesn't go to sleep so you might have background stuff going all night long and it's not charging enough to keep up.
Galaxy Nexus GSM