Originally Posted by dubbau
I see your point I must be missing something with the physics I just though of a external circuit that wouldn't draw on the first would some what work I mean even if you could not recharge the entire battery (Same amount of energy spent to make the momentum) you would at the least extend the range by some percentage...
There's no such thing as free energy. It has to come from somewhere and you never get it back at 100% efficiency. You would be taking power from one battery pack and transferring it to the second battery pack minus the energy you used just to move the car and the inefficiencies of your alternators putting drag on the car.
You could use regen and get some of the braking energy back, but that's it. Many hybrids and ev's already use regen to recover breaking energy. Basically, instead of transferring all your momentum to heat in the brakes it uses the ac motor as a generator when stopping to transfer some of the energy back into the batteries.
Look up conservation of energy. You should probably refrain from making any more posts until you understand it, but that's up to you.