Uhhh... the obvious question is why on earth would you randomly leave your phone in DFU mode to begin with. The ultimate answer I believe is no as DFU stands for "device fail safe utility" which I don't think will initiate the power circuit to charge the battery. Someone is welcome to correct me on this. Worst case... leave your phone in DFU for a few hours on the charger.. then restore and see if it's fully charged. Nothing that can't be answered by a little trial and error.