". . . mid-mounted cryogenic storage tank . . ." Now this is fun. Use liquid ammonia and a hydrogen generator and I'm IN. But hydrogen gas or liquid is nuts! Bob Wilson
No word on venting for that tank in the article. This BMW Hydrogen 7 - Wikipedia, the free encyclopedia had a liquid hydrogen tank that held 8kg. left parked, a full tank would be empty in little over a week.
The BMW rear looks a a little like the front of a Toyota. Bob- Ammonia is hazardous substance I don't think that's the way to go, do you?
I spent one summer working in an ice plant that used ammonia as the refrigerant so it has my respect. But I'm not that concerned with it. Compared to hydrogen, I would much rather deal with ammonia: hydrogen ammonia gasoline metric 1 -259 -78 -50 to -40 melting C 2 -253 -33 37-162 boiling C 3 0.07 0.86 .77 density at boiling Liquid ammonia can exist under modest pressures compared to hydrogen and with ordinary metals. Upon decomposition to N{2} and H{2}, the N{2} can be dumped overboard. By weight, 3/14 = 21% hydrogen. The toxicity is primarily from the hydroscopic nature. But that means 'hose it down' to handle any that hasn't evaporated and floated away. It burns the eyes but once washed or out of the area, no problems. Bob Wilson
Ammonia also becomes a potent base once dissolved in water, but it doesn't need sensors to let people know there is a leak. It will also burn in an ICE. So the early infrastructure can be supported be cheaper tech cars. The same could happen with hydrogen, except the tanks will be expensive no matter the tech driving the car.