Is hydrogen a volatile medium? Think Hindenberg. Think Hindenberg exploding.
How do you contain volatile hydrogen? In a cell form.
Does the weight of the cells cause problems? Yes, heavy vehicles are not as nimble and fuel effecient with system.
Where do we get hydrogen today? By a process using OIL. It is an expensive process.
I'll stick with gasoline.
Think Hindenberg, but think right. The hydrogen did not explode, it didn't even start the fire.