Original post by: Rany ,
1- Bad battery. Get one from iFixit. If you cheap out you'll be back to square one very very soon. DON'T pry against the board to remove this or any battery. 2- Battery disconnected. 3- Missing or bad gas gauge (tiny filter located between the battery connector and the metal shield next to that connector). 4- Corrupted software and DFU restore requires to fix it. 5- ALL OF THE ABOVE - yes sometimes it can.