Battery EV is high-capacity battery + engine + thermal management system for the battery.
Hydrogen EV is fuel cell + low-capacity battery (for smoothing out peaks and recuperation) + engine + thermal management system for the fuel cells.
BEV have low price per km (here it's about 1/4 compared to gas cars), but lower range, while H2EV have higher price per km (in Germany where there's actually infrastructure available, its about the same price per km as gas car) but higher range, so it can make sense for some use-cases, like long-range buses or whatever.
You could even build Plug-in Hydrogen EV with medium capacity battery and have BEV-like usage where you charge at home but still get 1000 km range if necessary - it seems needlessly complex, but it just means adding bigger battery and charging port to H2EV, so it can make sense.
It might be in the future. Here (EU) and now (2019), they cost as much as BEV, while fuel costs as much as fuel for ICE, giving you the worst of both worlds.
We're not going to run out of lithium any time soon, current supplies are limited only by the fact that it's only been desirable for a few years. There's a LOT of lithium mining capacity coming online now or in the near future.
Hydrogen was a dead end in 2000 and it's only getting deader.
1) There is zero elemental hydrogen on Earth. We currently get it mostly as a byproduct of....fossil fuel production. The other option is to split water into oxygen and hydrogen, but obviously this takes more energy than the resulting hydrogen could ever produce. Makes you think why don't we just use this energy to recharge batteries instead of making hydrogen with huge inefficiencies. It only makes sense if you have nearly free energy that you can dump into the process and don't care about loses.
2) Hydrogen is the smallest molecule in existence - meaning that it escapes through any container you put it in. A 70kg pure lead bottle only holds about 1L of hydrogen, and all of it will evaporate within couple months naturally. And as it does so, it makes the metal brittle. So "producing loads of hydrogen for storage" is not a great idea either.
Sure, but for a given amount of "free" solar you can drive a pure BEV 2-4 times as far as you can drive a fuel cell car, and the BEV will also be a better car. If you have infinite free electricity then hydrogen is potentially viable but since we discovered LiIon it's always inferior to batteries.
I do not think having called anyone Musk fanboy, but you seem to have been hurt or felt concerned wierdly :)
I did say that Musk hates the idea of Hydrogen car, and that might not be only for technical reasons.
> compressed hydrogen is extremely dangerous
Lithium battery is also well known dangerous. Dangerous enough that they are now banned into airplanes
> Hydrogen cars already require a battery.
False claim, supercapacitor on the long term can very likely do the job as a "buffer" after the fuel cell. And they are cheap to produce.
Supercapacitor that "battery-eletric" car also need for their "fast 30min charge" btw.
> I do not think having called anyone Musk fanboy, but you seem to have been hurt or felt concerned wierdly :)
You offered that the only reason they opposed fuel cells was due to "Elon Musk propaganda." The message was crystal clear even if the word "fanboy" itself was not used. :p
> I did say that Musk hates the idea of Hydrogen car, and that might not be only for technical reasons.
Maybe so, but the technical reasons alone suffice.
The biggest problem is that hydrogen is a zero-carbon bait and switch. Hydrogen from water costs 2-3x as much as hydrogen from cracking natural gas, for fundamental thermodynamic reasons.
Also fuel cells are no more than 50% efficient, because physics. This means the theoretically best possible hydrogen fuel cell car has worse well-to-wheel or panel-to-wheel efficiency than today's existing electric cars. Ouch.
> False claim, supercapacitor on the long term can very likely do the job as a "buffer" after the fuel cell. And they are cheap to produce. Supercapacitor that "battery-eletric" car also need for their "fast 30min charge" btw.
Where to begin?
- The size and mass of supercapacitors makes this a non-starter. Seriously do the math, it's quite bad.
- Supercaps are not cheaper than batteries per kWh. Quite the opposite.
- Supercaps are not needed for 30 minute charging. Tesla cars achieve this already without supercaps.
- Adding supercaps to EVs wouldn't make the battery charge faster anyway (other than quickly charging the small buffer). To get a lot of benefit you'd need to replace the entire battery with supercaps, and again that's not realistic.
Hydrogen cars were dead long before Elon Musk weighed in.
I hope Formula E adopts Nawa's ultra-capacitors. It will make the cars better. The big benefits will be a lighter battery pack and stronger recuperation in braking.
I think you covered most of my objections, the only thing I'd add is that the expensive catalysts have (or had? surely it's improved?) a sharply limited lifespan, so your $60k fuel cell could only run for 1000 hours before requiring a full rebuild.
Basically these "H2EV" things are EVs with a range extender, and the fuel cell range extender that they're using is in all ways inferior to a biodiesel or ethanol fueled range extender.
I was going to say this - Toyota gave up on batteries after building the Prius.
Their hydrogen fuel cell is clearly not the way the industry is going. So are they going back to batteries, the tech they said would never be commercially viable?
H2EV don't "burn" the hydrogen, because fuel cells are much better than engines that burn stuff in cylinders. So you end up with electormotor and fuel cell.
And since you can recuperate into fuel cell and fuel cells aren't very good at providing big short peaks of power, it makes sense to add a battery to smooth things out and to store energy when braking.
But the battery doesn't need high-capacity, because it's just a temporary store of energy. It's a very different battery technology than what you find in a Tesla or Kia e-Niro or whatever.
In the end, Toyota H2EV (Mirai) is basically 1) electromotor from Lexus hybrid 2) battery from Prius 3) Fuel cell.
