The only imaginable use for hydrogen fuel cells is storing and transporting energy, which crystals and lapotrons already do magnificently. I don't really see where else you'd go with them other than what the electrolyzer already does. With a stack of water cells you can store an amount of energy rivaling lapotrons for super cheap. I think that's a pretty decent use.
A hydrogen vehicle is a vehicle that uses hydrogen as its onboard fuel for motive power. Hydrogen vehicles include hydrogen fueled space rockets, as well as automobiles and other transportation vehicles. Some time ago, Toyota promised a hydrogen vehicle in 2015. The Toyota hydrogen car is still expected for that year. Widespread use of hydrogen for fueling transportation is a key element of a proposed hydrogen economy.
I don't know why you're telling us this story, but what the hell, I'll get into it.
I used to be a big believer in a future hydrogen economy, but I've become disillusioned since. The idea of superconducting megacables conveying gigawatts of energy around the planet, cooled by liquid hydrogen that would itself become energy at the destination was a fantastic dream.
The major draw of hydrogen fuel is a supposedly clean, 100% renewable source of energy; but in reality, it's no such thing. Hydrogen cracking plants would still draw power from the grid, and the grid will include oil and coal plants for the forseeable future, so you're only turning dirty, nonrenewable power into a different form and losing efficiency in the process.
Hydrogen offers no substantial advantage over gas-electric or pure electric vehicles; like electric, it has problems with power and range, but these issues are being addressed in both systems. The major disadvantage hydrogen has is that you would need an entirely new energy infrastructure to support it; a million or more hydrogen gas stations, not to mention all the transport and refining infrastructure.
With electric, all the infrastructure is already there. (and this is true in IC as well).
Hydrogen is kind of a pipe dream.