It would be nice if something like the propane-tank-exchange model could work with batteries. Unfortunately, while propane tanks are largely fungible, batteries aren't (there isn't enough of a value difference between tanks which are in perfect shape and those which are a little beat up to encourage many people to keep good tanks for themselves and refill them while they exchange crummy ones in the hope of getting better ones; the values of batteries, by contrast, decline considerably with use). I don't know how one could effectively prevent people from hoarding the good batteries they receive from exchanges while turning in crummy ones, except by adding a substantial "big brother" tracking infrastructure.
Battery technologies are improving, and it's possible that some sort of exchange system might one day become practical. Even if it does, though, I would think it might be good for a car to have multiple batteries and use circuitry to discharge one battery at a time during most driving conditions [so that when a vehicle had been driven about half its range, one could swap out half the batteries].
I’m not sure people would hoard them, because they need to ‘fill up’ again. If you’re not leaving town I suppose you would recharge whatever was in the vehicle, but if you weren’t happy with it, you could always go to the station and recycle it through. So I’m not sure it would be all that advantageous to hoard.
I have thought that it would be good to be able to swap your on battery packs at home. You could have one charging at home while you were at work. Come home and swap out.