[dirk94018]

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are much more interesting. They extend EV range to 600-1000 miles and enable 10-minute charging. If they work at scale, they kill hydrogen for cars, trucks, and probably short-haul aviation too.

[defrost]

The path of most interest to many is Renewables -> bulk hydrogen as storage -> electricity grid.

The bulk storage method of interest is dissolved salt caverns: https://news.ycombinator.com/item?id=47160599

[idiotsecant]

Bulk hydrogen makes a lot less sense than pumping water up a hill. We have thousands and thousands of sites throughout the country that would be great for pumped storage and require absolutely no advanced technology. They are buildable today.

[rfv6723]

Solid state batteries are overhyped because their production complexity makes them a pricing nightmare for the average consumer. Sodium ion batteries are the practical choice for short distance transport because they are affordable and charge incredibly fast.

When it comes to long distance shipping or aviation, the energy density of liquid fuel is simply too hard to beat. Fossil fuels will stay dominant for decades, likely evolving into carbon captured or bio derived alternatives rather than being replaced by batteries.

[nerdsniper]

Compressed hydrogen and cryogenic liquefaction also present explosive/BLEVE risks. Metal-hydride is probably the only reasonably safe-ish option. Other issues (like hydrogen embrittlement, leaking, slower flow-rate) are all very real challenges, but 'solvable'. Solving all of them at a price that consumers/businesses can stomach is quite debatable.

Batteries are just too good nowadays to expect hydrogen to receive the level of R&D and infrastructure investment to become at all competitive.

[_carbyau_]

> enable 10-minute charging.

I have a problem with the current physics of this. A car requires a LOT of energy to run. The electrical requirements "at the pump" are going to be pretty hefty for 10 minute charging.

Unless:

1. Reduce capacity requirements. IE Cars evolve smaller and smaller until they are practically aerodynamically efficient go-karts. A trend opposite of current affairs....

2. Charge for longer timeframes but swap in less than 10 minutes. IE standardise and replace batteries as needed.

I suspect that the "10 minute recharge" meme will be obviated by ridiculous ranges allowing us to then charge while sleeping instead.

[xbmcuser]

2-3 min battery replacement is already a thing in China for trucks. The largest manufacture CATL is also pushing for safety and compatibility standards so all trucks can use all truck batteries in future. And for charging they are building charging stations with batteries that are charged slowly but can charge cars fast. The electricity revolution is just picking up pace

[mikestorrent]

I like the idea of swappable batteries in theory, but in reality... well... that's a lot of logistics and a lot of potential for things to go wrong. Consider the swappable propane tank market, for instance; it's clear that returning cans need refurbishment and testing before you can give them back out to people. This implies it probably can't be just done on-site at a gas station.

They also weigh an absolute ton, so specialized lift equipment is needed; they take up space and will be very difficult to move around. So, are we expecting to stock a huge pile of batteries somewhere with an automatic loader/unloader that can handle multiple people at once with a quick turnover rate that can put away a 2000 pound battery? It's just too much infra, compared to a charging station...

And then there's the matter of the vehicle design; chassis rigidity is important and batteries, being a huge weight, need to be positioned properly with enough load bearing structure around them to support this. I'm imagining a hydraulic lift raising a 2000 pound battery up into my car; some massive brace needs to be attached below it to hold it up. Talk about difficult to get right; we've got harsh conditions like road salt and rust to deal with, and we have to make a fully automatable fastening device that can work at a random gas station with any brand of car... yikes.

You're actually much closer to the idea with the reduce-capacity idea. I had a Ford Focus Electric a while ago that had about 80km of range on a good day. This was more than enough for 90% of my driving; my old SUV handled the rest. Net carbon savings were huge; pity it was totaled in an accident or I'd have kept it going. Even at almost 10 years old it still kept a charge no problem and was a delight to drive compared to a normal Focus. My current EV has far more range but feels heavy and ponderous despite nearly 500 HP.

[vardump]

Very much simplified, a 10 minute charge would mean 6C charging throughout the curve. 100 kWh battery would thus require 600 kW on average. Right now the most powerful MCS chargers deliver 1440 kW.

So not impossible, as long as the battery can handle the current. It's obvious that charging technology is not going to be the bottleneck.

(A real battery would probably have a charging curve that slows down towards the end, so more than 6C would be required in realistic conditions.)

[idontwantthis]

It's always been clear to me that Hydrogen is not the future, because the car companies that made hydrogen cars never tried to build a hydrogen fuel distribution system.

The main reason EVs are a thing is that Tesla built the supercharger network. The fact that Honda or Toyota didn't do that for Hydrogen is the reason it has not been a serious fuel alternative. And they probably didn't do that because they always knew the economics would never work out and were never serious about pursuing it.

[toomuchtodo]

Electric heavy duty trucks are already here, with existing battery technology.

> In 2020, nearly all new trucks in China ran on diesel. By the first half of 2025, battery-powered trucks accounted for 22% of new heavy truck sales, up from 9.2% in the same period in 2024, according to Commercial Vehicle World, a Beijing-based trucking data provider. The British research firm BMI forecasts electric trucks will reach nearly 46% of new sales this year and 60% next year.

> The share of electrics in new truck sales, from 8% in 2024 to 28% by August 2025, has more than tripled as prices have fallen. Electric trucks outsold LNG-powered vehicles in China for five consecutive months this year, according to Commercial Vehicle World.

> While electric trucks are two to three times more expensive than diesel ones and cost roughly 18% more than LNG trucks, their higher energy efficiency and lower costs can save owners an estimated 10% to 26% over the vehicle’s lifetime, according to research by Chinese scientists.

https://www.ap.org/news-highlights/spotlights/2025/chinas-di...

https://electrek.co/2026/01/24/hybrid-and-electric-semi-truc...

https://www.electrive.com/2026/01/23/year-end-surge-electric...

[tjmc]

Looking forward to seeing solid state batteries for aviation, but the scary part is that they get heavier when they discharge as oxygen from the air turns into solid oxide.

[AnthonyMouse]

Isn't that good for aviation? Makes it relatively less expensive to carry reserve energy you don't expect to use, don't have to pay the weight cost during takeoff when weight costs the most energy because you just charged the battery and once you're at cruising speed more weight is just neutral momentum.

Probably the least convenient thing would be if you had to land and take off again somewhere without recharging.

[svnt]

My favorite part is that high pressure hydrogen leaks can auto-ignite in air.

http://www.icders.org/ICDERS2007/abstracts/ICDERS2007-0255.p...

[adonovan]

> Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, ...

Second smallest, after monatomic Helium molecules (which have similar problems of storage, embrittlement, and leakage).