There are different plans with options to own batteries or rent them or both. Last I checked they were in the 3rd Gen of interchangeable batteries that work with 1st Gen units but expand power capacity.

(Originally 1.35kwh now 1.75kwh; I just googled)

So, 6 would get about 30 miles range in a car and be at the modern 300v minimum if run in series. 8 would be enough for the average American commute of 40 miles (round trip).

While that math does work out to 60 battery packs to get a 300 mile range, I don't think that much range would be necessary since the battery swap time is so much faster than recharging. That would mean building out a fairly massive battery swap network, but it's already been done successfully in some countries.