3 ms·
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 i
by yholio 5y ago
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.
- _hypx 5y agoEven 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.
- yholio 5y agoIndeed, 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.
- _hypx 5y agoIt’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.