[toss1]

I think the trick is not to swap the whole battery

Instead design in a space for a secondary battery, maybe 40% the capacity of the main battery. Make those standard and swap-able.

Now, you can use the car as ordinary in either the one-battery or two-battery mode, with the 1B config being more nimble handling with less range, and the 2B config more range. In any case, you can then enjoy rapid-swap of the standard 2nd battery, or maybe just rent one for a long trip.

This also helps the automakers keep their proprietary designs on the main battery for differentiation. The 2nd battery could go in the extra trunk space or something...

[stetrain]

But if you are talking about faster partial-capacity refills during road trip stops, we already have that.

Current batteries charge way faster from 0-50% than 50-100%. The curve really starts to fall off above 80%.

I usually try to plan my stops so that I’m arriving with 5-10% and charging to 60-65%. With 250kW chargers that results in a ~15min charging stop.

I don’t think the costs of development, impact to vehicle design, and infrastructure would make sense for swaps just to replace what is already a 15min charge.

[toss1]

True, the differential will reduce as we get even higher-amperage chargers and batteries w/higher C ratings.

Yet still, being able to get 40% in 3 minutes is still better. I'd also see little reason that a properly configured trunk couldn't hold a pair of 40% battery units. Kind of like carrying jerry-cans on the back of a rover, except you can just plug them in...

[stetrain]

Jerry-cans don't weight 400lb