Why did all the car manufacturers start producing electric cars and no one thought of hydrogen?

They are focusing on EV because they are the much better choice. Hydrogen is far less energy efficient (as a system) than batteries, will have a lot more complexity, and has serious safety issues. Then there is a glaring lack of infrastructure to make and deliver the stuff.

The fuel cell, and hydrogen as a fuel is only a promising technology if you are in the fossil fuel industry. Right now they are holding it up as a Shiny Thing (tm) that Will Be Great (sm) and you can get one Real Soon Now (R) What they are doing is trying to convince/distract you that instead of your next car purchase being one of those “horrible” EV, you buy one more gas burner, and next time you can get a wonderful fuel cell vehicle. The big problem they have with electric vehicles is that given the possibility of wind and solar, there will be significant amounts of transportation happening, without them making a profit from it.

Hydrogen may be the most common thing that we know about in the universe, using it for transportation has a bunch of negatives. Right now, most, (90%+) of hydrogen sold comes from steam reforming of natural gas. This has its own heavy carbon burden, one molecule of CO2 released for each 4 atoms of hydrogen. It takes energy to make the steam, etc to separate the hydrogen. The resulting hydrogen contains less energy than the methane you started with, and takes 4 times the space to store. But hey, if fuel cells do become common it's a new market for natural gas. It will also mean that there will be a bottleneck, as they would have to add capacity to existing refineries. Half of what they do make goes to make ammonia, primarily for fertilizer. So we might have a repeat of ethanol in gasoline diverting resources from the food supply for transportation.

Yes, you could extract hydrogen from water. The theoretical best you can do on the extraction is about parity with the energy content extracted, but real world it will take about 25% more energy. A kilogram of hydrogen contains about 40 kWh of energy. The theoretical best for breaking up the water is slightly more than the amount it contains, but in the real world the best out there is more like 50 kWh. Oh yea, we don’t have any factories to do this built yet either.

Next you have to store it. The current technique is to compress it to 700 bar. (10,000 psi American). Compressing the amount equivalent to a gallon of gasoline takes 12 kWh to run the compressor. This mostly shows up as heat, that you have to deal with. You never recover this energy, which will take my middle of the pack EV about 60 miles. Despite the 700 times reduction in volume, it still takes 6 times the space of that gallon of gas. Just where are you going to put those tanks? Again a point that the fuel industry likes about hydrogen, even if they aren’t the ones making it, it holds onto another fragment of the industry, you have to go to special places to buy some, and wait while it is transferred to your car. Again, we don’t have the compression equipment available, and there are under 20 copies of the dispensing systems available nationwide. We will also need a bunch more of the specialized trucks for moving high pressure gasses.

Contrast that with electricity, where it’s the rare household that doesn’t have access to it, and if needed, those places, since they are so isolated, have plenty of space to install a solar or wind generation. Dispensers for electricity can be as simple as a $20 outdoor outlet, or a $100 high power socket typical of campground RV hookups. $3–600 buys an EVSE for home use, for $1–4,000 you can get one for commercial use, (adds accounting). Even a level 3 high speed charger is under $50,000.

To contrast a dispenser for gasoline (what everyone calls the pump) is $20,000 plus it’s share of the storage tanks. (Cost unknown). The price of a hydrogen dispenser is supposedly brushing a million each.

Ok you want motion from that hydrogen, you could burn it which would net about 20% of the energy as motion, or you could send it to a fuel cell, and get back about 35% of the energy. So we throw away a third of our electric power just on a compressor, then we get at best 35% of that back when we convert it back. So just the overhead of the storage system, means the energy at the terminals of the fuel cell, is just 22% of what we started with.

So, you can use methane sourced hydrogen and get at best half as far as just making electricity with it and putting it in batteries, or if you are starting with water and electricity, you would get at least three times further by feeding it into batteries instead. If you have methane, you could just make minor, and time tested changes to the engine, and run the stuff directly, it's only a 40% volume penalty over gasoline, and the carbon footprint is the same running the engine as making hydrogen, and since the pressure in the tank is lower, you waste less power stuffing it into the can.

Range will be an issue with hydrogen, given its poor energy density, and conversion efficiency batteries already have it beat on volume/kWh, and are improving. Tanks that can hold 700 bar are heavy, so it won't be that far ahead on weight.

Batteries are now at $150/kWh, and expected to drop further. It takes platinum to make the catalytic membrane in a fuel cell. I doubt they will catch the prices of a kWh of batteries anytime soon. And you won’t be battery free with the fuel cell, because of cost, they are all hybrids, with the fuel cell charging a small battery pack.

Finally there is safety. Right now if you perforate a battery pack it smoulders into flames, no bursting into them like liquid fuels. There is some time to extract victims before the car is fully engulfed.

A high pressure tank is a missile just waiting its chance to show you what it can do. But unlike a tank of Argon or CO2, the stuff will form a flammable, and possibly explosive mixture out of what is vented. Break a fitting off your hydrogen tank, and you get two energetic events from a single failure. Right now cars running on or transporting flammable compressed gasses are barred from using some tunnels, particularly underwater ones. Even a RV with a 17 lb LPG tank for cooking will get diverted. (And tunnels still using human toll takers actually enforce it). If you have a crash with conventional vehicles, and get a fuel spill, you have a cleanup job, and some moderately high chance of fire. Do the same with a compressed gas tank, and especially in the enclosed spaces of a tunnel, an explosion is almost certain.

Another example. To support the backyard male burnt food offerings industry, my local drugstore is an agent for a grill tank exchange program. (Logo is an endangered, horned African herbivore, in blue) The tanks live in a mesh cage bolted to the outside of the building. Prominent on the nicely enameled sign, is the text: gas tanks not allowed inside the store. This is echoed by pre-printed, branded stickers on every door, repeating the admonition about bringing the bottles inside. But the real telling point is in front of the cage. They have a pair of concrete “jersey” barriers bolted to the pavement between the cage and the parking area.

Similarly, the local American Legion has a small scale bottle refill service tucked into the far edge of its parking lot. The tank is comparable in size to a small sedan. Surrounding it is a chain link fence, and on all sides there are concrete cubes more than a meter on a side.

So we have one group that wants to stick large high pressure tanks in cars, and run them around at speed on the highway. Then there are people that have been handling smaller, lower pressure, tanks for a while now. They put one ton waist high concrete blocks between their cage of tanks, and a parking lot with a 10 mph speed limit.