It would take like 15 or 20 minutes to charge your car between runs, that seems kinda stupid. You have no need whatsoever for that much capacity. You would pretty much get 3 runs out of your controller batteries before needing to replace them. And since I doubt you'd run it down every time, most of the energy would be wasted as your car runs out its charge sitting on the desk after you're done with it.

Seems wasteful.