With a fossil fuel car, if you run out of gas, you could take a small jerry can and hop on a cab to the nearest petrol station for small fill-up that would last tenths of kms. With an EV, a detachable battery the size of a small briefcase could serve the same purpose. Preferably, the battery is designed to a universal standard so that any passing EV could loan to you as a favor.
Generally, the batteries in these cars are locked so that only the manufacturer can service it because the charge could kill or maim you if you mess up changing it.
I like the solution at lot and 1 minute down from 5 minutes in extremely significant because the line that will form outside these things can be quite significant. If there are 5 cars in front of you, it's the difference between 5 min and 25 min.
The challenges I see are:
1. Cost. How much is it to maintain that building-sized machine? That needs to be passed on to the consumer during battery changes.
2. Space. A small building-sized facility can only get 1 car at a time. In the same space, you could put like 18 gas pumps. You can stack a few on top of each other and add car elevators on the outside.
I see the most potential to this being a supplement to at home charging. Meaning that most people going from work to home and on errands should be charging their batteries at home but if you are on a road trip or forgot to charge up/electricity outage in your area, you can come here. Otherwise, with the car density in China's major cities, even with a major build-out of these stations, the lines might be terrible and wrap around the parking lot.