[BrianG]

While you could technically do that, there are disadvantages. The biggest being that there is no way to shut off the ESC. Even when not doing anything, they still draw some small current and will completely kill your battery if left on for a few days (or less). I suppose you could apply an offset charge to cancel out the effect of discharge, but that seems like way more work than any benefit. I too would suggest using a decent connector like Deans, Traxxas, or whatever.