The only way I see this being remotely viable is some service where I "drop my battery off" on my way to a destination - use their batteries for the duration of my trip, then pick my battery back up at the end of it. Otherwise: absolutely not.

Who in their right mind would take a brand new car with a battery at 100% health, go on a long road trip, and end the trip with a used battery of questionable health? When it's upwards of $20k for a new battery, you could have left your house with a $20k battery, and gotten back home with one that's at 60% health and worth a fraction of that.