Let's think quantitatively here. First of all, hydrogen doesn't squirt out of a hole in the ground. We have to make it either by stripping a hydrocarbon fuel, or by electrolysis of water. In the former case, the carbon component is generally released as CO2, and the amount of hydrogen energy is considerably less than one would get by simply burning the original fuel in an engine.
With electrolysis, the round-trip efficiency from electricity to hydrogen and back to electricity is less than 40% if you are lucky. (Even an ordinary lead battery is good for 85%.) Hydrogen is great for welding, filling buoyant balloons, and talking in a funny voice, but not for propelling automobiles.
Fuel cell cars are essentially pure EVs, except instead of having an imperfect battery there is a small chemical plant to convert hydrogen to electricity. The infrastructure problem of lacking hydrogen fuel stations is much worse than the lack of EV charging stations for EVs and there's the question of where the hydrogen comes from. Using clean renewables to produce hydrogen is extremely inefficient, energy intensive, and therefore expensive. Using fossil fuels to do so cancels out the reasons for having FCVs in the first place.
If a breakthrough to cheap, clean, and sustainably produced hydrogen occurs (and before EV batteries become practical for the mainstream) and these little chemical factories (fuel cells) can be made reliable, safe, and affordable (a huge order), then someone please wake me up then.
Liz, the issue has been, and continues to be, cost. I believe the infrastructure would eventually spring up if the cost model were right. That hasn't happened, though, because the cost is still too high. One industry analyst recently told me that the unspoken goal in the auto industry is to get the vehicle cost below $50K.
Most electrics get less than 300 miles per charge. While a half hour charge might be fine for daily commutes, it's way too long for serious travel even with pit stops. Swapping those huge heavy batteries? If they can be dropped from the bottom of the vehicle frame they can also be damaged by collision with foreign objects as has been recently demonstrated in the real world. I can just see trying to release a battery whose, frozen under ice, clamps won't let go. And the frequently exercised high current connectors will become another point of failure especially if moisture can get in during changeovers. Just thinking about the handling and or robotics required and the drive through shelter to enclose this operation, the massive scale of parallel drive through stalls in comparison to standard gas station islands, makes me question the efficiency or efficacy of battery swapping.
"Hydrogen is great for filling buoyant balloons, welding specialty metals, and talking in a funny voice, but not for driving your car to work and back."
That would be helium, not hydrogen.
The practicality of hydrogen as a fuel for internal combustion engines was demonstrated in the 1970s and 1980s by Dr. Roger E. Billings and his Billings Energy Corporation (founded in 1972). He promoted the concept of the "hydrogen homestead", whereby solar and wind energy could be used to split water and store hydrogen under relatively low pressure in tanks containing metal hydride. Billings Energy had pretty much worked out the details of the technology that would allow an individual to live completely off-grid and produce all the hydrogen necessary to light and heat one's house, cook, and provide hydrogen fuel for one's automobile to commute to a job and run errands. As I recall, threats were made on his life and he sold the business in 1985.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.