That's just down to charging infrastructure no? Sure, there are physical limits to how much electricity one can move in a given time, but we are nowhere at those physical limits.
So it's just down to infrastructure in the end. If there was infrastructure to quickly and reliably charge EVs, ICE would only have niche advantages.
Honestly, _averaging_ 300 KW is probably within a factor of 2 of the highest we'll do for light vehicles given economic (how much electric distribution infrastructure can an 8-32 stall charging station have?) and practical (how heavy and stiff can the charging cable be?) limits.
It's unlikely EV charging speed will ever match existing ICEs. Relatively long recharge times are an intrinsic trade-off of BEV technology which needs to be engineered around, mostly by having enormous and heavy batteries.
Does this require further work? Yes of course. We are definitely not there yet, and we may never get there. But let's not pretend that this is an insurmountable problem.
On the engineering side:
- Swapping requires standardization of batteries across models and manufacturers. To accommodate different vehicles the batteries will need to be rather small so most vehicles will need multiple swapped every time
- Requires more space and weight because the battery cannot be structural. This will reduce the overall range of EVs
- Connectors for high voltage, signalling, cooling fluid, and high strength mechanical rated for thousands of cycles in the face of road grime and poorly maintained swap robots will not be small. Cooling system contamination will be a serious concern.
On the financial side:
- Batteries are expensive, how do you track and reclaim them across the entire continent? What about theft? Destruction insurance?
- With swappable batteries the incentive is to store them at 100% then run them 100% to 0%, which is especially bad for battery longevity
- How do you deal with batteries swapped at different 'swap' networks?
On the user side:
- What if the swap station is out of batteries when you need them? Are you always gambling on holiday weekends that you won't need to sit for hours charging (if that is even possible!)?
- Since some batteries will be more worn than others, how do you deal with constant variability of range because maybe last week you got a new set of batteries and next week you'll get an older set with only 80% capacity left.
- Are you allowed to charge at home? How is the wear from that charged?
- Did I buy a battery with my car, or are cars no longer batteries included? If my car came with a battery, how do I know I get it back? Do I get paid for the wear other users put on it? Do I need to retrieve my battery from the same station on the way home after a road trip?
That's just off the top of my head. I'm sure there are others. Most of these issues are solvable with unlikely levels of corporate cooperation or immense levels of excess capital expenditure. However, they all cost money and will reduce the economic viability of battery-swap EVs versus every other vehicle type.