I mean, its not the point how to recharge the battery. The point is that we have an over unity system because the current is minimal. The voltage makes the whole job.
OK, you obviously don't understand what "over unity" is.
Over unity refers to a system that produces more energy that it consumes. Such a system violates the laws of thermodynamics and is theoretically and practically impossible to create.
The voltage and current are totally irrelevant here - all that's happening is the transformer is converting high current/low voltage from the batteries, into low current/high voltage. The power in the system stays the same. You cannot increase both voltage and current, as you would need more power from somewhere - there is no such thing as a free lunch.
A similar thing occurs in a
Van de Graaf generator and a
Tesla Coil.For the device to demonstrate over unity, there would have to be a way for it to run forever. So the batteries would have to be continuously recharged by some method, or the batteries would have to removed (with the system continuing to run).