Here is a video of how Better Place used to do battery swap. Technically, they did fine. Financially, they are bankrupt and closed. This automation is very expensive, and it works only in perfectly clean conditions of Israel. I cannot even imagine how badly such a robot would fail with a car that travelled a few miles on a dirt road. It would be hard to protect 10 sq. feet of the bottom of the car from splash and from loose gravel.
Well, the love of money can really bend a conscience. Hey they proved that somehow, somewhere, it can be done. Dry desert. But with the mess that is a typical US car environment, apparently won’t work. I could see it requiring a washing before the swap, but not for normal US dirt to render it impossible.