A typical Mirai fuel consumption is 0.76kg/100km in similar driving conditions with a Tesla doing 15kWh/100km, so real world fuel density is 20kWh/kg - with a corresponding decrease in COPV density. You would then almost halve that density to take into consideration the whole electricity generating system, cell + cooling + the supercap or NiMH assembly that handle transients and regen braking etc.
So the density advantage of Hydrogen is limited, half to a third the battery mass with comparable volume. Not a game changer in 2010, and certainly not now, when everything else is against it.
The much improved and high performance fuel cells have been just around the corner for two decades. In the meantime, BEV sales have outstripped H2EVs one thousand to one, growing exponentially every year. How could anyone even consider buying a H2EV when the reliability of infrastructure is a joke even in the most mature US market [1]? Considering electric chargers are becoming ubiquitous and anyone can install one in their own home?
I think one needs to smell the roses, it's not a festive occasion for H2EVs.
For the COPV alone. If we can ignore the associated hardware, a flask with some lithium could do 11kWh/Kg, if only it were to combust with the surrounding air in a spontaneous Li-Air cell.
Aside from mass, volume is fundamental on a terrestrial EV, it reduces storage capacity, comfort and range at highway speeds. That's why a Tesla can have two trunks, while the Mirai is limited to just 5 Kg of fuel.
Even with everything included, that's still 600 Wh/kg or so. BTW, an EV with everything included really only has around 140-160 Wh/kg. It's still far short of what hydrogen can do.
The Mirai also stores around 186 kWh of LHV energy (220 kWh HHV). It's storing a fundamentally larger quantity of energy than comparable EVs.
Indeed, but it does so by filling every inch of space. There's no front trunk, and the backseats and trunk are relatively cramped. Further improving on that pits you against the laws of physics: even if you could, say, safely double the pressure in the bottles, you waste more and more energy - compression is already a big part of the round-trip inefficiency of H2EV.
Meanwhile, EV already exist today with similar range - Model S or Mercedes EQS, with something like 90% solar cell to wheel efficiency, and battery chemistries are only getting better.
It’s a modified Lexus in the end. It’s not optimized. If well designed you’ll get more room and range compared to a similar EV. The Hyundai Nexo is an example. Also, not every EV has a frunk, like the EQS.
So the density advantage of Hydrogen is limited, half to a third the battery mass with comparable volume. Not a game changer in 2010, and certainly not now, when everything else is against it.
The much improved and high performance fuel cells have been just around the corner for two decades. In the meantime, BEV sales have outstripped H2EVs one thousand to one, growing exponentially every year. How could anyone even consider buying a H2EV when the reliability of infrastructure is a joke even in the most mature US market [1]? Considering electric chargers are becoming ubiquitous and anyone can install one in their own home?
I think one needs to smell the roses, it's not a festive occasion for H2EVs.
[1] https://www.motortrend.com/reviews/2021-toyota-mirai-long-te...