Tesla tried that too (https://www.youtube.com/watch?v=H5V0vL3nnHY), but they only built one swap station and they decommissioned it a couple of years later. They claimed lack of demand and doubled down on supercharging instead.

A company named Better Place got a ton of VC funding to set up a battery swapping service for electric cars, and flamed out spectacularly.

Perhaps NIO can succeed where Tesla and Better Place failed, but I'm doubtful. OTOH, Shanghai is probably a great place to start.