A tesla battery bank runs about 1200lb...an RV will be drastically heavier.
There are some city buses that are electric but they have average speeds of around 20-25mph and peak speeds of 45mph. That means wind resistance is negligible and they get a lot of regeneration from braking.
Wind resistance increases with the square of speed, which means you will require drastically more power to run for even a couple hours and regenerative braking will be negligible (if you can even find a retrofit system). Then it will take a very long time to recharge (campgrounds, rightfully, will consider charging substantially more if they catch you charging the battery bank).
It's basically, not practical for a new build. For a retrofit, it's really bad.