I have had this happen before and went through 3 batteries, all puffed and dead. I changed the board and has never happened again, might have had sloppy soldering or something and have built 3 more dna 200's without incident. The usb recover would work a few times until battery gave its last breath at 0.0v and as i remember I had to let it charge at 0.05 amps forever up till roughly 1v till usb charge recovery will work. Mabey someone knows what the lowest voltage for a cell to charge via recovery. I wish I wouldnt have been ignorant and let it kill 2 max amp and 1 fullymax before I decided to change the board.