If you don't plan on leaving the car at hundred percent for hours on en,, maybe days, then there is no damage at all to even letting it go all the way. On a road trip, most of the time that I, at least, use the supercharger Network, I'm always going to go as soon as I'm ready. Generally I'm ready before the car hits a hundred percent. I never drop it below 100%, don't want to pay those idle fees!