Irrelevant. You're still limited by supply rates and feed wire heating.
LOL. No, you most certainly are not. Supply for the vehicle is from local storage, charged slowly over time, ready for fast discharge when needed; inevitable because of the requirement to move the load to the times when the plants have available generating capacity. You can't just pull at peak times, think about the consequences. What you're missing is the dynamics of supply. As for feed wire heating, that's absurd. At these lengths, and these voltages, it's simply not a problem. Then there's the obvious: you can always make the plug bigger, or use more plugs if charge rate limiting was a problem, which of course it isn't anyway for a vehicle in the weight range of a car, pickup or SUV. Commercial trucking might present some minor design challenges, but not serious ones. They're more likely to be resolved with conventional gearboxes than untoward amounts of raw power anyway. Now, an oceangoing vessel power plant, that might be interesting. However, then we have long times in port, so perhaps not even then.
Irrelevant. What, you think cars have multi-megawatt inverters and motors?
I know that with multiple high energy motors, motor peak current demands can be very high, particularly in the case of high power motors that batteries aren't good for, and that semiconductors can be arranged for very high parallelism.
10 years-ish isn't good enough for you?
Oh heck no, not even close. We own three vehicles; all are older than ten years, and none show any signs of needing anything more serious than the windshield wipers and tires needing replacement from time to time. I have no intention of replacing them in the next ten years, either, unless EVs real;ly take off. Furthermore, if the ones I have now were electric and UC powered, I'd just move the UCs to the next vehicle. There are plenty of vehicles on the road that are far older than ten years; the need to replace a huge battery pack at ten years has a serious impact on TCO and resale value (yeah, it's nine years old, in a year you're going to need a $10k pack. I'll give you the car for $500, how's that?). I expect to be able to replace the batteries in my vehicles with UCs, in fact, well before electric cars become common. Heck, I could do it now in the pickup, if I wanted to take up some space in the bed. The electronics required are trivial. It's tempting, too... -40 is quite a challenge for batteries, we have to keep a heating pad going under them in order to keep them working decently. Montana's not a great environment for batteries at times. I'd have to rig a cover for it all, probably lose 6 inches of depth in the bed. Hmmm. :)
The life expectancy of supercapacitors is identical to aluminum electrolytic capacitors
As it happens, I'm a collector of old audio gear. When kept in service, electrolytics run for many decades (lots of mine are from the 1970's, so that's 45 years so far) and they hold up, too. It's only when they are unused for long periods of times that they don't. Recapping is pointless if the unit has been kept in service -- I've put this to the test many times. The idea that their lifespan in use is ten years is a complete myth. Furthermore, check the cycle rate: the charge/discharge rate for a UC in vehicular motive service is doing so (perhaps) once a day. They allow for millions of cycles before any performance change is encountered. So use in a vehicle, as long as they keep being used, is many times the ten year underestimate. I've also got a bank of fifty of the early Maxwell UCs here in my radio room, they're well over fifteen years old and they're still just fine, every one of them. Because I *use* them. So I'm not buying any claims that they're much different than electrolytics (although I would expect that, given the unit cost, they'd be made much more carefully.)
Overheating of the supercapacitor can occur from continuous overcurrent or overvoltage charging.
Yes, yes, of course you can break them if you misuse them, but the relevant point you are ducking here is that an UC won't overcharge if a continuous supply is applied to them that is under their rated voltage. This simplifies charging system design enormously, and passes on zero aging and wear effects to the UC. Look at the various high power battery technologies and compare.
Show me a single type of ultracap which can be recycled at all.
Show me one in continuous, low cycle rate use that needs to be. Look on EBay. Search for them. Look at all the used ones pulled from equipment. Why do you think that is? It's because they're still perfectly good, regardless of what happened to the equipment they were installed in. Look in particular at the exact units offered for sale -- a very large number are well over ten years old. All of mine are; my initial curiosity resulted in a buying spree, and that eventually turned into the DC supply for my radio station, which requires about a kilowatt and a half when fully dialed up. I get a solid hour of runtime there, more without the linear running. Not a battery in sight. That's been working flawlessly since it was put into service just before 2000. I designed and built all the electronics (required to keep a steady 12v output as they discharge), there was nothing that had to be done that would raise any competent EE's eyebrows. UC configuration is fused parallel.
In short, please stop with the standard BS mythology of what ultracapacitors are, because it's just not in accordance with reality.
Well, you can say anything you want, but I don't think you've demonstrated any of this, and further, you're rather conveniently ignoring the current research, which (of course) is largely targeted directly at this application. But time will tell.
1 1/2 orders of magnitude worse volumetric energy density and 1 1/2 orders of magnitude worse gravimetric energy density
Yes, that's exactly what I was talking about. Are you actually ignorant of the rate of technological disruptions we've seen pop up in tech after tech? This area will require one. Which is exactly what I was telling you above, so it's kind of pointless to tell me back, don't you think? I think it likely there will be one -- again, look at the current lab work. If not, well then there you go. Again, time will tell. Your opinion, or mine, won't.