is there any safe form of producing hydrogen gas by electrolysis without any adverse affects. so you would run vehicles that first are filled with water, battery starts engine, engine starts electrolysis, as well as top up the battery (plus storage tank contents remaining of h2 of previous drive out)
h2 is then created and stored in a safe container,and pumped to the engine
so energy from the engine feeds the battery generates h2 runs the vehicle and so on
thus eliminating need for hydrogen stops
just fill up with water at your local station every few thousand miles ,and maybe purchase a new battery
storage tank replaced every so many thousand miles for safety if needed ,along side
anything else affected by h2 in the vehicle plumbing etc.
just a thought = so no need for vast storage or transport of h2 problems
all built into the vehicles instead