Let's take a look at a practical version of swappable batteries. I use 80VDC Greenworks batteries:
The extended run battery, 288 Wh, is on the left. The smaller 144 Wh batteries are on the right. But the right most one failed.
The problem is one or more cells have started corroding:
These are 18650 cells that I could buy on eBay for ~$40. Add to that a battery tab, spot welder, and a couple of hours and the 144 Wh battery would recturn to service.
Instead, I bought a new, 21700 cell, 288 Wh battery, $400, that is the same size as the original, small 144 Wh battery packs. Lighter than the large, extended run battery, it makes a lot of sense over several years of operation.
Fitting the 21700 cells in the same dimensions as the original 18650 cells is a neat trick. But 18650 cell chemistry has improved. The originals appear to be 2500 ma cells and I see 3000-3500 ma cells available. It makes more sense to let battery technology continue to improve and replace the failed 18650 with higher energy density, LiON cells within a year. So how does this relate to 'battery swapping?'
Notice the overhead of swappable battery packs. This adds weight and non-payload volume to the vehicle. These parasitic loads on the EV reduces their range and efficiency. They carry around extra structure. In contrast, the structural battery pack weights only as much as the minimum number of parts needed.
So I add swappable battery packs to hydrogen fool cells as another, dead-end technology. In PowerPoint or user forums, sounds GREAT. In real engineering, something less.
Bob Wilson