Elon demo'd it, but it hasn't seen the light of the day. Similar to his description of this robot snake that automatically plugs your car in. Lots of great ideas, but I think the more important thing is to get the cars out.I've thought of the hot swap able battery pack being a good idea too. Even if it you had to break it down into a few modules. (like you said, charge at a hotel room) Tesla at one point was showcasing robot operated battery swapping that was supposed to be faster than filling up a car with gas.