Hypx_

Even going by volumetric energy density, hydrogen is still higher than li-ion batteries.

You can make hydrogen tanks a structural member. They're made out of carbon fiber after all.

Modern fuel cells have extremely high power density. You can easily have >300hp in a car. Even higher for large vehicles.

Hydrogen could easily replace batteries in nearly everything. In fact hydrogen cars already have more (real-world) range and 5 minute refueling. You have to get down to laptops and cellphones before the complexity problems makes hydrogen less desirable. People are just deluding themselves by saying hydrogen can't make sense in cars.

It’s possible. A company called LAVO has made something of that sort.

At some point people will finally realize that hydrogen fuel cells are a type of battery. It’s made from literally water and has the highest possible energy density of any chemical battery.

Current fuel cell tech with compressed hydrogen has an energy density of above 1,000 Wh/kg. It's already far beyond what li-ion can provide.

Hydrogen is simple a better element to build a battery around than lithium. That and more availability and less dependency on rare elements.

A hydrogen fuel cell is the highest energy density battery possible. It doesn't how more advanced li-ion or a variant of it gets, hydrogen fuel cells will still have a higher energy density.

Furthermore, by the time you're talking about metal-air batteries you are basically build a fuel cell but with metals. Which is to say you're just building fuel cells that are fundamentally inferior than something that already exist.

We have basically created an inverted worldview. In reality, the li-ion battery is fundamentally inferior to hydrogen fuel cells, and any attempt to advance EV technology will inevitably produce a hydrogen fuel cell powered car.

It's cheaper overall since you don't need to worry about a heavy battery. This is already the case for larger vehicles: https://cafcp.org/sites/default/files/07-24-2020-Foothill-ZE...

This likely to be true for more types of vehicles as hydrogen gets cheaper.

The problem is that hydrogen has radically improved in the last decade, but batteries have not overcome it’s fundamental weaknesses. For instance, we are now see hydrogen drop to below $2/kg even with entirely green hydrogen. Fuel cells have also gotten cheaper and more reliable.

The efficiency argument might end up being the same argument made against ray-tracing in the 3D rendering world. In that instance, the upside of have correct lighting with a simple algorithm eliminated whatever upside you could get out of a faster but more complex rasterization system. Hydrogen could easily be the way to have a single simple technology that works in all transportation cases.

The simplest counter argument is that it’s just cheaper to go with hydrogen. People have created this narrative where “efficiency = cost” when in reality it’s more expensive to go that far in efficiency.

Which is why you use an extremely high discharge battery or super capacitor. There’s no real problem with the fuel cell itself. Something that will become even less of a problem when more powerful fuel cells appear.

A dedicated race car will absolutely blow away a road car. I don't think you're even aware of much slower the road car will be on a track.

Even though they'd easily run circles around a Model 3, this admission still proves my point.

Almost as much gymnastics as you're using here. Maintenance and fuel costs will drop for FCEVs too. Right now, battery buses are more expensive. More importantly, you can get away with much fewer buses and a smaller refueling footprint since each fuel cell bus has significantly more range and shorter refueling times.

Hydrogen supercars and race cars exist. It's matter of having a high enough discharge rate battery or a supercapacitor. It's a completely pointless argument to bring up.

Hydrogen buses are already cheaper to operate than battery buses and are more reliable: https://cafcp.org/sites/default/files/07-24-2020-Foothill-ZE...

Real world testing has already proven you wrong.

Nothing you said is true.

There's a world of difference between a 1.5 kWh battery and an 80 kWh battery.

These problems are also true for nearly every country except China and a few others. UK, Germany, etc., also import huge amounts of energy and they too will need a way of importing energy in the future. Furthermore, none of these countries have any meaningful supply of battery related minerals nor any substantial battery manufacturing capacity.

The entire concept of "worse is better" can be more accurately be described as "don't let the perfect be the enemy of the good." Simple, functional solutions are good ideas, and attempt to replace them with perfect ones are likely to fail. In software, that just means writing code using practical languages that are proven to work. It does not need to be written in the ideal language, especially if using the ideal language requires very specialized skills. Furthermore, you do not need software that solves every single corner case. Once you have solve the main problems and most of the minor ones, there's no reason to waste years solving the last few annoying issues.

As I understand, the byproduct of a carbon-air cell is carbon dioxide. This doesn't mean such a cell can't make sense, but it has some fundamental downsides that are hard to mitigate. It will requirement a very specific form of carbon capture where the result is hard carbon for such cells to make sense.

That might be partially true. Especially in the case of hydrogen-to-ammonia where the process of conversion is much more straightforward. However, storing hydrogen in salt caverns for years at a time is already proven. So further conversion steps might not prove any real value except where volume of storage is important.

All metal-air batteries have similar thermodynamic properties. If you can make a iron-air battery with good efficiency, than you can make a hydrogen-air battery with good efficiency too.

Since water is significantly more available than just about any other material, hydrogen-air cells should be the ideal battery for anything that isn't volume limited. Which is frankly a lot of cases. Unless there's some specific need for an iron-air battery where hydrogen-air can't be used, it's hard to conceive of a situation where we wouldn't use hydrogen-air.

Synthetic hydrocarbons are basically extensions of hydrogen electrochemistry. You are just adding carbon to the hydrogen made with the electrolysis step of a hydrogen-air battery. It's even possible to make a hydrocarbon-air cell such as direct-alcohol fuel cells or solid oxide fuel cells.

Hydrogen-air batteries already exist and work extremely well. I think we are approaching the end of people seriously trying to make a new novel type of metal-air battery. Stuff like these are probably the last of its kind.

BTW, hydrogen-air battery = hydrogen fuel cell, if you didn't realize that.

It's going to live up to the hype. It just didn't happen in that timeframe.

More info: https://www.youtube.com/watch?v=YJBzEYduKK8

It's the same idea of green hydrogen. Only hydrogen allows you to use pipelines instead of physically hauling everything. You also don't have to worry about the battery physically gaining weight as you fly.

Because aluminum-air batteries are not rechargeable, they're fundamentally inferior to hydrogen fuel cells (which work in nearly the same way!). At least with hydrogen you can refuel the airplanes with a liquid instead of having to use a physical battery swap. Also, even higher energy density that doesn't gain weight during flight.

Electric airplanes are increasingly just gadgetbahns of the sky. None of the are even remotely feasible, and reading the comments here it's clear that even if they did exist they'd be immediately disrupted by existing airplanes. I think it's time we stop giving them any more thought as they simply cannot work.

Hydrogen is guaranteed to be the future of energy storage. What we're seeing now is the normal "reaction" from established business that fear being disrupted. It's so predictable that it's embarrassing to even see people try to argue it away on a website like this.

Remember, people said the same thing about electric cars and they were wrong. This is just history repeating itself. In a decade, no one will seriously try to argue against hydrogen.

The next stage is hydrogen powered cars. All of the upsides of electric cars but none of the downsides.

Though I wonder... Some decades ago people made similar arguments with regards to C/C++ versus native assembly. That the only way compiled languages could approach assembly languages on performance was if the code was written in a way that the compiler could optimize. If it couldn't, performance would often tank.

But as compilers got better this become less and less of an issue. By today it has become very rare to need to write in assembly. So shouldn't history repeat itself? That JIT compilers will be so good that it becomes extremely unlikely that you'll hit the performance cliff.

That might've been true at the time. But what about today? Can't we use the higher settings for JPEG 2000? At least speed shouldn't be an issue now.

You should be aware of the death toll for the construction of the first transcontinental railroad. It's not something we can legally replicate.