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Tell HN: I think I found Toyota's battery
529 points by scythe on Aug 3, 2023 | hide | past | favorite | 203 comments
Recently there was a thread about a "breakthrough" in battery technology at Toyota.

https://news.ycombinator.com/item?id=36585327

Toyota has been putting out PR puff pieces about their "solid-state" (solid-electrolyte) batteries for years, but this story was unique in that it had a quote from Keiji Kaita, who holds some high-level role at Toyota. Anyway, I didn't think much of it, because there was no paper referenced in the Guardian article, which seemed to be the original source.

But while reading about something else, I came across the paper "A near dimensionally invariable high-capacity positive electrode material", published in Nature Materials last December:

https://www.nature.com/articles/s41563-022-01421-z

This paper, reporting a cathode that has very little (much less than normal) change in size or shape when charged and discharged, claims reversible storage with a solid electrolyte. It stands to reason that dimensional stability of the cathode is necessary for interfacing with a solid electrolyte, since if it swells and shrinks, it will probably detach from the electrolyte, and possibly damage it further.

Looking at the affiliations of some of the authors we see a number of contributors from the "Lithium Ion Battery Technology and Evaluation Center (LIBTEC)". A web search about LIBTEC leads to several articles from 2018:

https://www.cnet.com/roadshow/news/toyota-nissan-honda-libte...

which state that Toyota, along with Nissan, Honda and Panasonic (Tesla's major collaborator), have established this consortium to work on solid-electrolyte batteries as of five years ago.

So what does this thing look like? It's a vanadium–titanium cathode, Li8Ti2V4O14. Titanium is common; vanadium technically has a higher crustal abundance than nickel, but it tends to be spread across low-quality deposits, so production is low right now. A review considering the resource outlook for V-based batteries [1] was guardedly optimistic. 750 Wh/kg is great. Vanadium cathodes historically had a problem with high dimensional instability, but it appears that cocrystallization with titanium may have fixed that, and the weird properties of vanadium became an advantage in compensating for Li+ influx/efflux.

The use of a sulfide electrolyte pours doubt on claims of safety, though. It's reasonably likely that if water were to come into contact with the electrolyte, it could release highly toxic hydrogen sulfide gas.

Also, since the battery was developed in collaboration with other major automakers (and funded by the Japanese government), it's somewhat questionable to think it would give Toyota a major advantage in the EV race. But for the Japanese economy, which has been rather slow lately, it could be a boost.

1: https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10....




> 750 Wh/kg is great.

To put it mildly.

Energy density in the current leaders in that category, lithium ion batteries, 250-270 wh/kg. So, provided a similar or better ratio of watt-hours to unit of volume, we’re basically looking at tripling the energy storage of EVs or significant weight reduction, in the ideal scenario of this design being a safe and cost effective replacement for current batteries.


I think for the EV skeptics it’s easy to forget how fast battery chemistry has been evolving. There’s an common assumption that the EV status quo of 300 mile range at barely-affordable prices will continue forever, and therefore with all the woes surrounding charging and bad weather affecting range, EVs are dead in the water.

Ten years ago $30k got you 75 miles of range out of a Nissan Leaf. Fast forward to present day and you will spend less money before adjusting for inflation and get 259 miles of range in the same class of vehicle (Chevy Bolt EV).

When many automakers say they will only sell EVs by ~2035, it sounds a bit far-fetched, but in the context of the past 10 years it’s hard to deny the high probability that gasoline vehicles will make basically no sense by the 2030s on the basis of value.

Gasoline cars will simply cost more to own, end of story.


To me it all still comes down to charging infrastructure. The current state of batteries is good enough for me, but I live in an apartment and can't charge at home, and the availability/reliability local charging stations are a crap shoot, nevermind charging on a road trip.

But when (if?) I own my own house and can charge at home, I'll be in even with the current state of batteries.


My primary concern with the charging infrastructure is how well it will handle a large number of people taking emergency trips at the same time. How do you evacuate south Florida with an incoming hurricane, for example, when most people have switched from gasoline to electric cars?

That scenario pushes the existing fuel delivery infrastructure to its limit already, and electric chargers provide significantly fewer passenger miles per fueling minute than a gasoline pump does. In practice, a lot of emergency plans will need to be completely overhauled to not assume most people will be able to drive themselves out of the danger zone.


This is a good point and I think the answer is that solutions for in-place charging will need to be regulated or subsidized into existence in step with the shifting market share of electric cars.

The typical range of a fully charged electric car these days is sufficient to get out of the way of almost any predictable natural disaster. So the trick is just keeping them all fully charged at home. Any homeowner can in theory have a charger off their home power grid, but for folks in apartments and condos there will need to be a lot more than just a few chargers in the corner of the garage. There may even need to be street-side solutions. But it’s all doable and the engineering is straightforward.

People allow gas cars to sit with nearly empty tanks because it is so fast (and expensive) to fill them up. Electric cars are slow and cheap to “fill up” so the mindset and culture about it will change over time.


During Hurricane Rita in 2005, over 2 million Houstonians got on the road to avoid its wrath. It took anywhere from 12 to 36 hours to reach their destination.

Many ran out of gas but roadside assistance were able to fuel them up and get them going again.

https://en.wikipedia.org/wiki/Hurricane_Rita_evacuation


Well, the thing is that EVs are just “less bad” version of personal automobiles, which are a very inefficient way to get a large amount of people from one place to another.

Houston is a city that is so large that it should have frequent passenger train service to other metropolitan areas, but it doesn’t because it has been designed for cars and planes.

You can fit a lot of people in a train, and in emergencies even more people can occupy the train in standing areas.

When cars get stuck in traffic where they’re going <25mph their main flaw is revealed: the fact that you can frequently beat a car stuck in traffic using a bicycle.


> The typical range of a fully charged electric car these days is sufficient to get out of the way of almost any predictable natural disaster.

Maybe, and maybe not. The one time I had to do this myself, I started with a full gas tank and still ended up stopping to fill a couple of times. An evacuation is hardly the ideal condition for range, with lots of stop-and-go traffic. You need to not only get out of immediate danger but also find some safe place to lodge overnight that doesn’t interfere with the people behind you that also need to get out.


> There may even need to be street-side solutions. But it’s all doable and the engineering is straightforward.

That‘s true! Vienna, Austria has over a thousand street-side chargers already. They‘re tiny and right next to the parking spot.


Are batteries still on a roughly 3-4% annual rate of improvement? Or has that shifted? So,e of that will have been aerodynamics (the industry is slowly boiling the frog on styling vs aerodynamics) and motor efficiency, which has climbed a lot in the last 15 years.


In 8 years costs per kWh dropped from $732 to $151 usd-2022 [0]. Halving every few years but it's been slowing down.

[0] https://www.statista.com/statistics/883118/global-lithium-io...


energy density hasn't really changed for 15 years, price dropped a lot though, but price drop has also paused recently. There is no telling if any progress will be made or not. Maybe! Maybe not.


That doesn't sound right, so since nobody else has piped up I decided to actually try to find the answer myself.

Volumetric numbers from the DOE suggest it went from 55 Wh/l in 2008 to 450 in 2020, which a compound interest calculator tells me is about 20% per year. Which is an awful lot.

Physics world says 80Wh/kg when Sony introduced them in 1991, and 300 today (although someone above said 270 is what ships), which looks like about 5.1%. But the lab experiment numbers are substantially more than that https://physicsworld.com/a/lithium-ion-batteries-break-energ... and shows that the exponential curve was visible back in about 2014. These of course have little to do with production numbers. The bigger the breakthrough the longer it takes to commercialize (or the more watered down it becomes to be commercialized). That was the wisdom when Wall Street was interested in new battery companies.

5% means every 14 years power doubles. We've been flirting with electric vehicles at least that long.


This is because batteries are, of course, magical devices produced by chemE’s and only begrudgingly handed over to the EE’s, along with instructions like “do not puncture the pouch, or the magic spirits will get free and erupt into a vile flame which burns water.”

I am quite certain they are just doing alchemy and have tricked us all (it is of course well known that chemE’s are actually the cleverest type of engineer).


Actually, when demand for EVs goes up, lithium mining won't be able to keep up, so in the next decade or so we'll see steep increase in battery prices.


In the next decade you will see more reliance on technology that becomes cheaper than simply throwing lithium at the problem.

It's the same thing with many techs. In the 70's we thought we would run out of oil by 2000, and a lot of asshats in the 80's and 90's crowed about how stupid those so-called experts were.

What happened in the 80's and 90's was ground sensing radar found more oil, horizontal drilling found ways to access more of what was there, and zeolites saw widespread use as a catalyst to increase the amount of gas and diesel recovered from a barrel of oil. And over time production of zeolites made that process work better and better. It's very much like when Apple went to non-replaceable batteries. Battery life doubled in that model because 3 different parts of the problem got improvements. Density, volume, and power management all contributed almost 30% each.

Between "Oh Shit" and "Told Ya", we could produce twice as much fossil fuel as we knew how to do at the time. The same will happen with Lithium. Reduce, Reuse, Recycle and Replace.


That's not what Peak Oil means, but I think you know this. The cost of oil will never return to pre-2000s levels because meeting demand necessitates more expensive extraction technologies like shale and offshore. In that sense (the correct one), the prediction of peak oil by 2000 was remarkably accurate.


If you adjust by inflation oil is now cheaper than it was between 1980 and 85.


Isn't that cherry-picking? That was the peak of the oil crisis


As is food.


Some chinese car manufacturers have already moved to sodium ion for car batteries. It is quite funny to me when people bring arguments of how electric cars won't work they are unaware the rate at which things are changing in the space. And that their arguments have been invalid in 2-3 years but they read the article from 5 years back and then never bothered to update themselves. The same is the case for solar tech.


I remain skeptical until the products are real and affordable. No reason to buy an electric car now if they'll have potentially double the range in a few years.


By that logic it never makes sense to buy a computer. It'll be obsolete in 18 months!

Electric cars are cheaper to operate that gas RIGHT NOW, with less maintenance. No reason to hold off just because they're going to get better.


Companies literally made this calculus decades ago during the boom years of Moore's law when it came to purchasing computer hardware.

> Electric cars are cheaper to operate that gas RIGHT NOW, with less maintenance.

My timeline for owning a vehicle is 15+ years. I'm not going to buy something that is instantly obsolete. I'm also not going to buy all this vendor lock-in nonsense all these EVs come with. If they were basic rides with an electric drivetrain, sure, but they try to make everything the millennium falcon.

You should look up how much fun it is getting service and parts on a new vehicle nowadays. You're rolling the dice that you won't burn down your home and/or have a lawn ornament because you can't get parts.


I bought a Kia Rio, the cheapest EV I can buy in my country (Australia) is an MG4 for around twice the price (~$20k for the Kia, ~$40k for the MG).

I don't drive very much, under 10,000 km per year.

I've done the maths and for me an EV is more expensive over an expected 10 year lifespan.

Granted I drive significantly less than average, but fuel costs here are a fair bit higher than in the US so for a lot of people buying at the bottom end of the market it may still not be true that an EV is cheaper.


For a Leaf the dealers response to ‘where do I go to get it serviced?’ was ‘don’t bother, nothing to service.

That’s a slight exaggeration but not by much (diff oil needs changing and the tyres need rotating).

It’s amazing.


Isn’t that wildly dependent on the cost of electricity and gas in the area you live in?


Yet another problem that could have been avoided if government had had the foresight to enforce a technology-agnostic swappable battery standard.


The only real practical version of this would be an additional range extension battery that is towed. Or synthfuel+generator, or even hydrogen (and man, this is like the ONLY time I ever can see practical use of hydrogen). Which is also an effective strategy for semis / RVs / towing with EVs.

The way to get best range+efficiency out of an EV these days is cell-to-pack where the pack is basically integrated into the frame. I think it's on the order of 20% better range for 10-20% lower production cost. There's no way a standardized swap pack could match the engineering numbers of that, which makes it an economic no-go.

And by the time the swap standard was implemented, demonstrated, and platforms changed to it, it would be 10 years. Batteries with this tech, sulfur, alu-air, etc will triple the density for half the current cost by then. An EV will go 800 miles on a pack that is 2/3 or 1/2 the size/weight, and remember there's a pseudo-rocket equation on these big battery packs.


Yes, frame-integrated cells are optimal from a bang/buck standpoint. However, the advantages gained by using standardized swappable batteries would be overwhelmingly dominant in comparison.

If someone doesn't immediately and intuitively get that -- and you're hardly alone in that respect -- I've found that no rational, math-based argument will persuade them. The ship has sailed, your side won, and now we all get to deal with the consequences.

Batteries with this tech, sulfur, alu-air, etc will triple the density for half the current cost by then.

Exactly! But you will have to buy a new car to take advantage of them, because your current car was designed as a battery with wheels rather than as a drivetrain powered by a battery. It didn't have to be that way, but again... your side won.


Well with the "cushion" afforded by high density cells, the replacement standard may come back, or at least make it a reasonable repair.

The point is that to compete with ICE, you need the extreme integration to break the ICE point-of-sale cost advantage. I agree in a perfect world a swap would be so nice to have as an option, if only for a cheap repair or upgrade as you point out.

I think the other problem was economics. You buy an EV, a massive component of the cost is the battery, yet you might get a lemon battery next time you swap, and then the "swap service" refuses to accept it back. Yes the battery could be a service and never explicitly owned...

Also, it is hard to imagine such a massive component being swapped without extreme wear / damage on the swap site. Sure theoretically it should be solvable, but real world? people freak out over microscopic paint chips.

IIRC Teslas were originally designed to be swappable in some manner. But it was never done.

The other thing is that it will likely happen with semis I would guess, which have longer lifespans and invested value in the actual equipment.


I think the other problem was economics. You buy an EV, a massive component of the cost is the battery, yet you might get a lemon battery next time you swap, and then the "swap service" refuses to accept it back. Yes the battery could be a service and never explicitly owned...

That's always been the most frustrating point to argue against, I think. Batteries can be insanely well instrumented. You can tell exactly how much charge has been sent into the battery and pulled out of it. You can tell how old it is, and you can tell how many charge/discharge cycles it has undergone. When you get a 'lemon', you are not going to have a hard time convincing the refill station that (a) the battery isn't delivering the stated performance; and (b) whatever is wrong with it isn't your fault.

There is no reason any normal human being should feel any pride of ownership towards a car battery. No reason on God's green earth. It is no different from the propane grill cylinders you swap out at the grocery store, except that with the battery you can see its entire service history courtesy of the embedded controller. Like those propane cylinders, the batteries will indeed look pretty shopworn after a few months/years in the field. So? You pay for the gas you use, and you pay for the charge you move. That should be the extent of your relationship with a battery, IMO.


You got it, swappable batteries is the key to EV mass-adoption.

Do people care about range with internal combustion vehicles? Not really, if they can get between gas stations. It takes very little time to refill, and each vehicle (regardless of manufacturer) uses the same stuff.

The trouble is that standardizing when there is hot competition is very political. Things need to cool down a little before it can be done, and you don't want to standardize until designs naturally converge.

You don't want government to get involved early when engineering is involved.

EVs will be a pain until a standard emerges though. I can't wait until I can drive up to a station and get a pre-charged battery.


My thinking was always that the physical packages should be standardized -- think two 'AA's for a Miata and twenty 'D's for a Peterbilt -- along with the connectors. Also a rudimentary bus protocol to communicate the battery's parameters to chargers and loads, store usage history, keep track of expected remaining life, and such. But literally nothing else other than basic environmental and safety considerations. A battery must be recyclable in some form or fashion, will not usually set your house on fire, cannot explode under normal operating conditions, cannot emit more than X milliroentgens per hour, whatever. Other than that, no rules.

Don't standardize the chemistry, or the voltage, or the current limit, or the charging rate, or anything else... just make it fit. Then require the industry to adopt standardized power converters and chargers under similar auspices. For the hardware, don't specify voltage, don't specify cost, don't specify charging time, don't mandate anything except the ability to charge a particular class of battery.

Simply mandating the form factor, connector, and handshaking could have made all the difference. We would have manufacturers competing to see who could build the most economical and/or performant batteries, chargers and converters. Charging could take place at times and places that optimize efficiency. Filling up an EV could take less time than getting gas, not more. And there would be no chicken-and-egg problem to impede adoption, as we're seeing now. You would not be stuck with the batteries or the charger that your car came with.

We will kick ourselves for the next 50 years for not doing this.


> You don't want government to get involved early when engineering is involved.

Apple would argue the EU was stepping on their toes by imposing USB-C. Maybe whatever proprietary connector Apple comes up with is better in some technical ways. But that benefit has to be weighed against the emergent benefits of standardization.

Maybe 120V AC isn’t objectively the best. But isn’t it nice you don’t have to think about it before plugging into a wall? I think so.


> Maybe 120V AC isn’t objectively the best.

It is not indeed, 240V AC is better as you need only half the current for the same amount of power.


> Maybe 120V AC isn’t l objectively the best

Just like miles and gallons..


EVs with swappable batteries would be inferior to those with fixed ones in many ways (weight/size/aerodynamics) the swapping part and all the related infrastructure would be very expensive. I just don’t how could this ever be competitive with fast charging.


We don't need the government for this. Consumers could refuse to buy proprietary solutions.


Your sense of optimism is, well, inspirational.

Meanwhile, on this planet, the necessary standard didn't emerge from government or industry.


This depends on if battery production can continue to be scaled up by another order of magnitude. That's a very short period of time for monstrous growth in multiple industries, it's by no means a sure thing.


Are there EV skeptics? I don't think so.

There are average people and EV fanboys. It's just that fanboys call the other people skeptics.

EVs are in early adoption still, from my point of view. Try to pump it all you want, but EVs offer far less utility for a higher price, and they are more inconvenient.

Until the industry standardizes on batteries and stations offer pre-charged battery swaps, I'll hang on to my ICE machine.


EVs are quieter, smoother, higher torque, better accelerating, for simpler drivetrain, less maintenance.

I've seen so many TCO reports on Teslas being cheaper than new ICE cars, and that was before the Tesla price cuts and the insane inflation in new car costs in ICE.

As for the "new car cost", I suspect Tesla is already at cost-per-vehicle parity with an ICE, but Tesla is keeping a high margin on their cars. With sodium ion and high density LFP chemistries coming to mass production this year, ICE cost advantage's days are numbered. Supply constraints will keep ICE marginally cheaper for probably 5 years in some consumer car classes.

But "far less utility for a higher price and more inconvenience" is pretty much bunk. But I would keep an ICE if I was in the Midwest.


>> As for the "new car cost", I suspect Tesla is already at cost-per-vehicle parity with an ICE, but Tesla is keeping a high margin on their cars. <<

You are thinking last year when the auto market was out of whack due to COVID related shortages. Tesla's operating margin is down to 9.6% in 2Q 2023; compared that to Hyundai's 9.5% and Kia's 12.5%.

>> With sodium ion and high density LFP chemistries coming to mass production this year, ICE cost advantage's days are numbered. <<

LFPs are still limited to entry-level, low-range EVs because of low energy density and weight. The cost of LFP's is't that attractive when the price of lithium is above $20K.


>Are there EV skeptics? I don't think so.

Lots of them. They're really gaining traction in the UK (where I live) - so much so that I hear compete b****s every day about EVs, and I'm tired of hearing it. I'm on my phone so can't type all the examples but essentially I've heard every advantage of them being said to be untrue, and that ice cars are better for the environment, etc.

The right wing press in this country has a lot to answer for.


According to a quick googling, this would be enough density for for short range commuter aircraft to become viable.

https://theicct.org/aviation-global-expecting-electric-jul22...


Actually CATL announced a 500 wh/kg battery a few months ago. Solid state and aimed at the aviation market. Shipping this year apparently. There are a few other companies targeting that market. For cars, much lower density sodium ion and lfp batteries are what they are producing in volume. Sodium ion especially is becoming popular for the kind of cheap/modestly priced cars Toyota is famous for mass producing.

Those higher density batteries are great when cost doesn't matter (like in the aviation market) but cost is the only variable that matters when it comes to mass producing electrical vehicles. The game is not who can build the most ridiculous car for 100K but who can produce the most useful car for 10K. Toyota is going to have their ass handed to them very soon in that market unless they get their act together.

People that obsess over range are missing a few important points. With fast charge times, range matters less, and if your car is fully charged every morning, the times when you need to charge before you get home reduce to the rare occasions when you actually drive the cars maximum range in a single day. Which for the average driver isn't that often. The point of having a large battery is reducing those occasions to almost zero. If that matters to you, just spend more money and you'll be fine. There's no need for new batteries for this.

The point of a having a smaller battery is that the few times per year that you have to stop to fast charge them isn't worth the price difference in terms of time spent. Especially when that time is basically only around 30-40 minutes. Companies that operate vehicle fleets get this. They get the battery size they need, not the largest one. That's why most electrical vans have batteries that aren't bigger than those in cars. Smaller even sometimes. Smaller battery means more useful load. The reduced range is fine.

Toyota doesn't need a new science fiction battery, it needs battery production infrastructure producing batteries by the twh per year. Nothing else is going to enable them to mass produce cars at the same rate they are producing ICE cars. They are not building those factories yet. I'm not sure what they are waiting for at this point. But they are running out of time. Cheap EVs are going to be on the market pretty soon. They already are on the market in China. The main constraint for that is battery production volume. Some companies are investing in that as fast as they can; Toyota so far isn't.


For mobile applications wh/kg and wh/liter both matter, and they can vary independently. With the titanium electrode you’ve got a lighter battery per unit of volume. That said, a vehicle battery has to propel itself, so a lighter battery requires less capacity and thus a bit less volume.


It's within range of some of the sulfur techs I've seen in papers though. The sulfur techs appear safer and more abundant.

Both aren't commercialized either... For some reason, I suspect sulfur techs will go to market sooner.

What is apparent is that in 10 years battery tech will be in a much better place than it is now: 2x - 3x the density, safer, 1/2 or less the (inflation adjusted) cost. Sure that's not Moore's law rate, but that will be nonetheless revolutionary.

240 wh/kg has already been commercialized by Gotion in LMFP chemistry, so that's cobalt-free/nickel-free. 160 wh/kg sodium ion should utterly revolutionize city transportation, you don't even need lithium for that and it should be a 200-300 mile car (EPA not WLTP) or better.

IMO most car companies are probably chasing the high density LMFP and Sodium Ion for the next 5-7 years, and leaving nickel-cobalt for things that truly need it. The issue with nickel-cobalt is that the safety systems consume so much at the pack level that 200+ wh/kg LFP is basically the same density. And Gotion's 240 wh/kg will probably be functionally more dense at Cell-to-Pack densities as well as cheaper.

We still need that high density breakthough through, the US Market will probably demand 400 mile ranges (see Tesla range "fraud" story) for true mass market stupid driver adoption, especially for all those men that just have to drive a full size pickup and then buy things for it to tow.


Out of curiosity, What is the wh/kg for petrol?


Wikipedia says 13000 Wh/kg, but you have to keep in mind that due to physics, wear considerations, and emissions regulation, most cars are only 20-40% efficient. At a 20% efficiency, that's 2600 Wh/kg. This is further constrained by gear ratios, meaning not all power is available at all times.


Exactly. Gasoline is much, much more energy dense than Li-Ion batteries, but in terms of dollars per mile, an electric car is 2x-4x cheaper to drive than an ICE car. That's because an internal combustion engine wastes the majority of gasoline's energy as heat, while electric motors use most of the battery's energy to move the car.


> That's because an internal combustion engine wastes the majority of gasoline's energy as heat, while electric motors use most of the battery's energy to move the car.

I guess that depends on your perspective and/or where you live.

I rented a Tesla in December once and was freezing the whole drive. A gasoline engine generates extra heat you can use to heat the cabin, whereas an electric car needs extra heaters (which IME weren’t working that well in that old Model S)


Heating the cabin was a known problem with older Teslas, especially because resistive heating reduced range significantly. Newer Teslas use heat pumps which are much more efficient.


> an electric car is 2x-4x cheaper to drive than an ICE car

It hugely depends on the cost of electricity. Last year some European countries (Netherlands IIRC) had those so high, that it was actually more expensive to drive EV than ICE.


You can optimize this with the right electricity contract. Time of day pricing ("dynamisch tarief" in the Netherlands) combined with charging during the cheapest times can make a big difference. And as a bonus to society, you help to balance the grid.


> This is further constrained by gear ratios, meaning not all power is available at all times.

CVTs enter the chat.

> At a 20% efficiency, that's 2600 Wh/kg.

Hybrids do better, of course.


CVTs enter the chat, but it's mostly to ask when they'll be replaced so you can use them again.

(I don't remember details, but we decided to specifically avoid cars with CVTs because of reliability issues. Sure enough, the only person I know with a CVT is having belt slipping issues. Seems like certain manufacturers were switching back to dual clutch arrangements)


My understanding is that the Nissan CVTs weren't outfitted with a large enough radiator, and that the resulting overheating is what tended to kill them. I don't think there's anything inherent about their design besides the insufficiently large radiator that would cause failures more frequently than non-CVTs.


Drove a Suvaru with CVT for 100k km. Never had any issue. Never heard of anyone having issues with CVT (from Subaru).


https://www.google.com/search?q=Wh%2Fkg%20of%20gasoline

Fuel Energy by mass (Wh/kg) Energy by volume (Wh/l)

Diesel fuel 12,700 10,700

Gasoline 12,200 9,700

Natural gas (250 bar) 12,100 3,100

Body fat 10,500 9,700


About 12,000

https://batteryuniversity.com/article/bu-1007-net-calorific-...


Obligatory XKCD: https://xkcd.com/1162/


Which works out at ~21,111,111,111 Wh/kg


At that energy density, can't they just wrap the entire smaller battery in 2 layers of ceramic and steel or something and just side-step the entire safety discussion OP is mentioning?

Yes, I know it's probably a silly solution :-)


If they could coat, or layer it, in a reactant or catalyst that made the hydrogen sulphide has less harmful or toxic it may work, so if the battery is damaged some of the toxic gas will be reduced to something less harmful.

Maybe a chemist would know if this is possible


Not silly at all, and that might be exactly what they do!


The premise is that the enclosure is already somehow breeched. Squeezing a battery is bad and it makes bad situations worse.


The thing is, batteries can weight half a ton. At triple the energy density they could almost armor plate it to tank levels. I imagine most of us aren't under Javelin attack during road trips :-p


Funny but there's still corrosion, cracking, and holes to connect wires to the battery.


Because weight affects range, you could keep the same amount of energy and increase range at the same time as the battery would only weigh 1/3 as much and be maybe 400kg lighter


400 Wh / kg is the threshold that makes VTOL high altitude (20+ km) electric aircraft feasible according to Elon Musk in one of his interviews (from memory, I might have some of that wrong).

Advantages: no runways needed at airports, can get back some energy on the way down through regenerative braking, more efficient propulsion and less air resistance at higher altitude (electric motors don't need oxygen to function), no pollution from combustion.

Sounds amazing.


The state of the art for VTOL right now is around 100-150 miles with much lower density batteries. The most efficient ones actually have wings and transition to flying like a regular plane. Larger batteries will of course help and they are actually hitting the market this year at around 500wh/kg. Bigger batteries will follow in a few years. The future is now.


Hey scythe, write a blog abut this.

This seems like semi-decent conjecture that'd get a lot of pull with the electric car crowd on the Fediverse, and you'd get a fair number of eyeballs pointed in the same direction.


A Tell HN is basically a blog post right? Permalink, comments, it’s got it all. There’s even an RSS feed.


but here you can't blast readers with a newsletter signup modal


Gah, I hate the internet on this timeline.


Make it a thread on X


Who says that HN is not a great source of outrageous humor?


WHO has been saying a lot of controversial things lately.


It's greyed out and hard to read.


If you use Firefox, Reader View is pretty nice.


I hadn't thought of that (though I do use FF Reader to avoid ads), though here I was thinking of a writer selecting a blogging platform.


I guess it can be. To me it's more for calling attention to a current event (api shutting down, breaking changes at a service, privacy concern, etc). Kind of like a PSA. Using it as a blog post feels inappropriate to me.

But checking the guidelines and FAQ, there doesn't seem to be anything to actually imply that it can't be used that way.


HN is like a blog, except that you don't have final cut.


So it's an immutable and non-fungible blog.


modulo the trust you have in the admins and hosts, yes.


Not really, I treat it more like a forum.


> it could release highly toxic hydrogen sulfide gas.

How bad is it in real world conditions? Because from what I'm reading it's not the "it makes you sick" kind of toxic, but rather the "it kills you in seconds" kind of toxic.


There’s no way to concentrate energy without creating some danger. Gasoline is quite dangerous but we drive around with tanks full of it now. Natural gas and high-amp electricity are dangerous but we have them coming into many houses.

So I would propose the question shouldn’t necessarily be, “how bad is the worst-case scenario”—it’s pretty bad for all energy sources. I think a better question is “how reliably and efficiently can we prevent or mitigate the dangers.” That will go a long way toward determining its commercial viability.


Current lead acid batteries can do this as well. Smells awful and pretty unsafe situation. H2S is quite dangerous but it’s rare that they’d create an IDLH situation as long as there’s a bit of breeze.


i'd be surprised if lead-acid batteries produce detectable quantities of hydrogen sulfide; isn't their sulfur bound up in an extremely stable oxoanion? still, https://web.archive.org/web/20161005164308/http://www.wesh.c... certainly doesn't sound like sulfuric acid


Humans are _very_ sensitive to the smell of H2S. Unless you meant that it might produce enough to kill your sense of smell, which is possible.


no, i meant i don't understand how you get from sulfate to prussiate at room temperature


I've discovered damaged lead acid batteries in equipment by following the rotten egg smell back to it's source. Twice, both small current 12V DC batteries.


Yes this was my initial reaction: what if a tesla battery comes in contact with water? What degree of "more dangerous" are we talking about?


MSDS for H2S - https://www.airgas.com/msds/001029.pdf

The Occupational Exposure limits are fairly low 'ppm' numbers, and LC50 is 712ppm for 1 hour. (That is the concentration at which 50% of the exposed rats died.)


Someone else pointed out LD50 is ~700ppm

It's unlikely you'd be exposed to this level for any period of time unless the battery ruptured into the car, underwater, with the windows up, in which case you have bigger problems. You're unlikely to to see 700ppm in an outdoor situation like a car wreck or battery malfunction on the highway during a rainstorm. Atmospheric CO2 is about 450ppm for comparison.

Ammonia is a superior refrigerant (widely used in industrial circles, and causes no ozone depletion, is biodegradable, etc) but not used in residential applications because it's highly toxic if there's a catastrophic seal failure and not vented outside, despite the fact that humans are very efficient at smelling even the slightest ammonia leak.


I think H2S is somewhat bigger of a safety risk than presented here.

For example, check out this case where what you describe (battery rupture) happened, killing both occupants from H2S inhalation:

https://web.archive.org/web/20161005164308/http://www.wesh.c...

And this was only from a starter battery, not a battery sized for vehicle locomotion.


It's interesting that Porsche put the battery under the driver's seat (in the cabin? unclear). Wonder if that made it more dangerous. Are modern EV batteries also in the passenger area or in their own little armored section...?


It was probably put there for weight distribution as Porsche would be more likely to optimize for that despite the user inconvenience it may cause


Possibly for a Carrera, but for a Cayenne? Despite the Porsche brand, that isn’t anywhere close to a sports car. The platform is shared with the Audi Q7 and the VW Touareg. It’s a tractor with nicer seats. The weight of a battery fitting under a driver seat would be similar to a big shopping run, so weight distribution wouldn’t have been a consideration.

Manufacturing logistics probably played a bigger role.


My Land Rover Defender had the battery under the seat as well.

But hey, there are so many holes in the car it’s basically permanently venting…


As excited as I am, there are some kinks in the supply chain that may need some extra taking care of [1]. Although this incident involved relatively few electric vehicles on open sea, it would be even more difficult to contain with larger shipments. Modular battery installations and separate fireproof(ed) shipping are options that need to be considered.

[1]: https://apnews.com/article/cargo-ship-fire-netherlands-envir...


Cars are often in tunnels, could be dangerous there?

For comparison purposes, note that indoors CO2 will go from 400 -> 1000ppm+ rather quickly if its not ventilated

According to this source [1], CO2 went from 400 -> 3000ppm inside a car cabin in 30mins, which is ~86ppm/min just from breathing. I could easily imagine a gas inside a car leaking at a faster rate and reaching 700ppm in a very short period of time.

[1]: https://www.co2meter.com/blogs/news/high-carbon-dioxide-co2-...


HS is funny stuff. Does nothing then zap, ur dead.

UK figures for safe working concentration in air, from memory, hydrogen cyanide 11ppm, hydrogen sulphide 10ppm


I remember synthesizing H2S in high school (for chemistry practicals, I think). I made the mistake of attempting to smell it. This was for a fraction of a second—but during that time, I could feel the individual bubbles of gas entering my nose; and I almost passed out.


Rotten eggs smell is just about everything you can get from this kind of experiment.

Now if they scale it up. but at any scale that makes sense economically you can get suffocated by just about any gas you can think of. Like helium or hydrogen.


H2S is also a byproduct of crude oil processing. The nose is easily overwhelmed by the smell even at low concentrations, and it becomes hard to notice before it strikes.


Depending on concentrations required for consequences a smelly gas is much safer than something like CO


I believe you go noseblind to hydrogen sulfide very quickly. [1]

[1] https://dodtec.com/news/the-potential-dangers-of-hydrogen-su...


Perhaps "safer than CO" is fair, but "much safer than CO" may be a bit of a stretch. H2S is the #2 cause of fatal chemical inhalations in the workplace, behind CO:

https://www.bls.gov/opub/ted/2019/fatal-chemical-inhalations...


That's an interesting find and some nice sleuthing you did there.


I remain an EV skeptic because of the flammable electrolyte in Li batteries. They did a good job of protecting the battery pack and managing possible thermal runaway. But reading some EV crash news, I noticed one aspect of EV fire is particularly frightening: the speed of the fire and thoroughness of the fire burning. If the crash is severe enough to cause fire, it's usually within 1 or 2 minutes before the fire reaches the driver seat and then it'll burn it down to skeleton and the firefighters can only stand by and wait for it to burn out.


This will be neat if it works but really there isn't going to be a huge market for 500+ mile cars vs the cost savings of getting a 300-400 mile car. The exception might be road-trippers and people who do a lot of towing but I suspect that is a much smaller population than people tend to think.


If it could only reduce the weight of current EVs that would be a win. Most electric vehicles weight 1000 lbs or more than their ICE counterparts, and in the extreme case of the Hummer, the total weight is over 9000 lbs.

Vehicles seem to be continuously ballooning in size, so whether that continues or eventual legislation forces more reasonable sizes, higher energy density would be very welcome.


Yes this is the real win. Lighter smaller batteries. Better efficiency and easier to design around for safety and maintenance.


If it allows a smaller and cheaper battery (hopefully in the longer term, less size = less expense) then it should make lower capacity small city EV runabouts more attractive. Right now the price floor is unattractive.

Many households have two cars, one for errands and one for work/travel, so if that's true it helps on both accounts.


When will this meme die? A Model 3 is very comparable in weight to an Audi S3. The Hyundai Ionic 5 is comparable weight and interior volume to a Toyota Rav 4.

The Hummer is a monster either way and is not a good sample.


I feel like that's quite a stretch of the word comparable.

The Model 3 is 14% heavier than the Audi: https://www.edmunds.com/car-comparisons/?veh1=401999985&veh2...

And the Ioniq5 is 35% heavier than the RAV4: https://www.edmunds.com/car-comparisons/?veh1=401958795&veh2...


And the Audi is already on the heavier side for vehicles of that size. Mainstream non-'luxury' sedans of comparable size are often 3200-3300, like Accord/Camry/Altima, and the construction of these vehicles is a more equal comparison.


S3 is heavy because it has 4wd and a bigger everything compared to a lower trim model. The same as the vw golf 8 starts at 1300kg, but my R model is in the 1500 range because it has 4wd and other things like adaptive damping that make it heavy


AWD is available on the Camry for an 86kg penalty. But yes, every part adds weight. That's why Teslas have spartan interiors and less noise deadening than other vehicles in the price range, they're spending as much weight as possible on the batteries and not the rest of the car.


From Google: Model 3: 3,862 to 4,048 lbs Audi S3: 3,527 lbs

9-14% seems comparable IMO and worst case roughly half he mentioned 1000 lbs.


The difference is around 250kg. Witch is a lot for a small car. My source is adac. But if you don't go to a S3 and are OK with regular A3 with smaller engine those start at 1300 kg.


You are comparing the heaviest Ioniq to a lighter trim of Rav 4. If you compare models more similar in price the difference is significantly less.


I went to Edmunds and went with "Most Popular" from the drop down when choosing the trim level.


They're not "comparable" at all. You're probably comparing the lightest model 3 (which you cannot buy anymore, the newer models are heavier) to the heaviest Audi A3 model on the market otherwise they aren't "very comparable"

Same for the model S, it's on average about 200kg heavier than a BMW 5 series across the range from most basic model to heaviest on both.

If a car has a 500kg battery, and tech improvements can make that 200-300kg for the same range that would be quite good. Handling improves, safety improves, the suspension can be simpler and in the end also range in stop&go traffic would improve with less weight.


The floor for EVs is very high.

In Europe people frequently buy compact cars.

Let's take VW Golf as an example. The lightest version of the current model weighs 1300kg, more or less.

The EV equivalent, ID.3, weighs 1800kg. That's 500kg extra (!) which is almost 40% more.

That's an insane amount of extra weight for a small car.

The percentage difference becomes less for bigger cars, so I imagine that's why some Americans don't notice it as much.

But for the rest of the world (95% of the world's population), that's a huge deal.


Meanwhile, the BMW i3 weights between 1245 kg to 1441 kg, depending on configuration, battery size, and presence of optional range extender engine, showing what is possible when companies bother to optimize for weight savings.


The i3 is a carbon finer tub design which is both extremely expensive and not uniquely applicable to EVs. It's a very cool design but its an extreme outlier and it isn't a realistic bar to compare against for companies trying to make money on mass market vehicles.


I doubt the i3 was profitable, which is probably why they discontinued it. It was basically a sort of production concept car.


The Audi is 3,527 lbs, where the Model 3 is 4,048 lbs. The Tesla is a bit longer and narrower, but they're both big cars.

The Rav4 FWD is 3370 lbs, where the Ionic 5 standard range FWD is about 4,000 lbs (the SEL is 4,300).

If the best examples are "only 500-700 lbs heavier" I think there is still room for progress. Rounded, that's the rough 1000 lbs I suggested above.

Electric cars are, in aggregate, simply heavier right now— with implications for crash safety for everyone (especially those outside that vehicle). Any progress toward increasing energy density (and vehicle size) will confer a net benefit to society.


...a net benefit to society, outside of those parts of society who live in icy and snowy conditions a good chunk of the year. In these circumstances, we appreciate the extra weight.


It’s not a meme. Battery electric powertrains are heavier than ICE + fuel equivalents.


Everyone here so far is comparing different models, but you can just compare the exact same car to remove (most) other factors.

2020 Kia Niro LX (1.6L petrol engine): 3,100lb

2020 Kia Niro Touring (1.6L petrol engine): ~3,250lb

2020 Kia Niro EX (64kWh EV): 3,854 lbs

Batteries are heavy.


Maybe the S3 can afford to add more insulation compared to the Model 3? I mean Teslas aren't known for good road noise isolation so if they do reduce battery weight they can add some more for the insulation for example.


Whereas Audi are known for excellent noise isolation, road, engine, to the point that in some models they pipe in engine noise because it's almost too isolated.


I always bought into this "meme", in part because just about every EV review I've seen mentions having to compensate for the extra weight which makes those cars less performant at times, so decided to look it up based on your quoted vehicles here, and figured I'd save anyone else the same search:

A 2023 Rav 4 has a curb weight of between 3615 and 3775 lb [1]

A 2023 Ioniq 5 has a curb weight of between 3968 and 4663 lb [2]

So a difference of between 193 and 1048 pounds between the two. That's actually a lot less than I expected, at least on the low end. 193 pounds is basically equivalent to just having one extra person in the car.

As noted in replies, though, these _do_ take into account different drive trains, so the comparison is not not great from the start.

[1] https://www.toyota.com/rav4/2023/features/mpg_other_price/44...

[2] https://www.hyundaiusa.com/us/en/vehicles/ioniq-5/compare-sp...


Not to devolve into splitting hairs, but your minimum range is comparing the heaviest premium AWD ICE vehicle to the FWD-only standard model electric, and the electric is still heavier.


Yeah, I missed that there were the two lines for the Ioniq 5 weight based on the drivetrain, and a column that was not obviously hidden with my window size, my bad.


Your numbers seem off...

Base models: 3,370 vs 3,968. Flagship models: 3,800 vs 4,663.

So 600-850 lbs differential. Not 1,000, but not just an extra person.

To be fair, the Hyundai does seem larger (12" longer wheelbase).


Yeah...I messed up. Damn window size and two different drivetrains for the Ioniq. Side note, web design sucks.


You don't have as many small cars in the US. Small EVs are MUCH heavier than small ICE cars. Think 30-40% heavier.


Are there any EVs with Honda Civic or Accord or BMW 2 series weight? E.g. <3500lb? Even a Leaf seems to start at 3500lbs now.


The Mini Electric is down there. Weighs more than gas, and one of the reasons it isn't long range, would push up the weight too much.

The current generation of battery tech is just a little heavier than would be competitive to ICE on weight. Gasoline holds a lot more energy than a battery can, but the engine is heavier. If/when battery density is able to double (and this solid state tech is 2x-3x current battery, so it would be a game-changer), you would have very similar car weights. This seems to be one of the reasons the big trucks are first, adding a thousand pounds to a 6000 lb. truck isn't as bad as adding that to a car half the weight. I expect we will eventually see vehicles that weight less than the ICE counterpart that get a reasonable range, but hard to say when battery tech advances that much.


BYD Dolphin is 1285-1450 kg depending on which options you pick, which is in that range


Here's some vehicles it's much closer to in weight than the audi:

https://www.edmunds.com/car-comparisons/?veh1=401999985&veh2...


What are you on? Having battery with 3x battery capacity will be an absolute game changer. This will do a lot of good, if it gets into production. For one thing, it will make EVs competitive with diesel, which will be s huge win for getting us of oil.


People will absolutely choose the longer battery span to rid themselves of range anxiety. I agree, it’s a terrible take.


IMO people mostly want longer battery span because current batteries take a long time to charge. Toyota has claimed that this battery will charge very fast, in which case range will not be as important as it is now.


The additional capacity might be wanted in cold climates. The massive range drop when running the cabin heater plus slow charging in cold environments definitely makes me pause when considering an EV.


Let's be real here.

If you live in any kind of cold-ish climate (below 10C) and want comfort, imagine a super common scenario:

- heating on

- air temperature below 10C

- highway speeds, so a steady speed of ~130kmph

- car costing less than €30k

Well, guess what, there are barely any EVs costing less than €30k in Europe, and even if there were, their range would be 200km or less under those conditions.


I’ve found that the range of my EV is overkill in summer and about right in winter. I live in Minnesota, USA where the winters tend to be cold.


First time I encountered range and overkill in the same sentence. Does your car contain breakthrough battery technology? Solid state maybe? Also, is electricity plenty cheap where you charge?


I agree with the previous commenter. If you level 2 charge at home you have to drive a pretty preposterous distance to ever have range issues. Road trips are another story, but they are infrequent.


I believe that such additional capacity will also be very well received by the ongoing hybrid airplane projects.


Real world usage is you only get to use ~70% of the stated range on a road trip, so we're really talking about 350 miles of range, which is, as you say, what most people actually want.

Why 70%? You obviously don't run the battery to zero, 10% is a common amount of buffer to leave. And then when you DC fast charge, the rate of charging drops dramatically around 80%, so people don't charge to full.

These are for ideal conditions, add in any sort of weather and the range drops again as you run a heater, etc.

Living in the Bay Area, driving to Tahoe in the winter without a mandatory recharge should be the gold standard.

It's not an unusual use case, "only" about 180 miles, and yet there aren't any EVs that can do it confidently because going uphill in the cold with aerodynamic-destroying ski rack is really hard.

A car with 500 miles of fair-weather range could probably do it?


Well the Lucid Air with the big battery could probably make that drive no sweat, but that’s out of reach to almost everyone.


Just people who go on road trips with 2 or more mountain bikes need this. This is not theoretical, a Model Y has its range ruined with 2 or more mountain bikes attached to the exterior. Like ~140 miles max on our trip with 4 mountain bikes. And then you tend to go to more remote areas so that makes it even worse.

So yes, our family is eagerly awaiting a 500 mile range ev


That's fair, but a truck with the same payload and rated range will do much better at hauling bikes.


A gasoline car can charge from 0% to 100% of its range in 5 minutes. It usually takes longer to take the slight detour and line the car up with the charge port than it does to fully charge the car. Recharging this kind of car does not damage its most expensive part nor does its fuel tank shrink.

The newest electric cars take a half hour to do this (a non-trivial amount of time) and only go about 2/3rds as far (less on the highway), so if you actually want to go somewhere you're taking on about an extra hour of charging for 6 hours of driving. Recharging this kind of car damages its most expensive part- the fuel tank- and it shrinks every time you charge it (whether quickly or slowly).

Now, if the car had 1600 miles of range, then a half-hour charge time and the slow shrinkage of its gas tank is more acceptable because you're getting approximately the same rate of recharge per minute (as it would be if the 200-mile range electric cars charged as fast as a gas car does). With a range or charge time like that, the other inherent disadvantages to electric cars are muted to a massive degree (a 20% range degradation isn't as big a deal for a car that can still go 1200 miles, and a 30% range reduction in cold months isn't as big a deal if the car could be charged in 3 minutes).

But neither of those things are currently true, and that's in large part why these kinds of cars don't really sell unless they're known to be rolling gimmicks or transformative in other ways (the electric trucks that let you run power tools off their batteries are the best example of this). Which is why Tesla's cars are the way that they are, and why every other major manufacturer who doesn't have a good idea of how to sell their inferior cars take the "look, we can do a massive screen in our car too just like Tesla" approach (and fail specifically because they aren't Tesla), or they just keep developing really good gas cars (an approach currently favored by the Japanese companies).


The market for gas cars will be dead in 10 years. It has all the signs of a technology transition and it will be absolutely brutal for all car makers which aren't ready. The range argument won't matter because people rarely drive distances exceeding 200km/120 miles in a single day.


Many people do. And even if they don't, charing a car every day if you don't have a charger at home or office will be very painful. Imagine that you have to tank theICE car every day, even this would have been irritating.


People like having extra capacity even if they scarcely use that capacity. This is why the F150 is the best selling car in America. Not to mention its better in general to have extra battery capacity than you might reasonably need today, as it will degrade with age, or temperature.


It's also why the F150 lightning appears to be an absolute flop: Its range goes to crap when you're towing, and people who want F150's at least think of themselves as people who want to be able to tow. (Actual towing with F150's is likely low, but most people who buy one, want to have the option.)


I thought it was a flop because it was basically impossible to actually buy one due to availability?


And they had battery issues early on that gave EV skeptical people an easy out to ignore them.


> people who want F150's at least think of themselves as people who want to be able to tow

I've only found this to be true on the internet. In the real world, it is much less common.

Lots of people realize that their truck is just the commuter and home depot stuff hauler.


At least it still performs well at the "Home Depot stuff hauler" part. A sedan is absolutely impossible to work for that use case.

(Ok: I'm a bit defensive. There's a concerted Internet effort over the past year to paint all pickups as a status symbol without justification, as if every empty bed or fresh-from-the-car-wash truck is proof that the owner doesn't need it. Even if you just move furniture every so often, I totally disagree with the sentiment. If I can afford two vehicles, a pickup and sedan would be a good combo; for now, just a pickup is good.)


But if you only now and then, getting a rental for this is much cheaper. Or just get delivery, even cheaper.


That isn't necessarily true. Rentals can be really inconvenient and surprisingly expensive.


The real world is the domain of empiricists. Rationalists rule online.


I wouldn't be surprised if people had resale value in the back of their mind. Tacomas are another popular truck but the top trims with the largest engines certainly command a premium and hold their used value better than the perhaps more economical 2wd 4 cylinder tacomas.


The few times you tow, you typically need full range, or what do you try to say?


If your range is shot because you're towing, it's probably a lot worse to have to recharge at a public charger with your boat on the back than it is to stop at a gas station. Keeping in mind of course that the limitations of charging mean you're also having to do this dance more frequently.


If I had asked people what they wanted, they would have said a faster horse. -Henry Ford

This is analogous to how people thought nobody would need a 100 GB hard disk on their personal computer when 1 GB hard disks were the norm.


500+ miles means I can just charge up on the weekend and not be bothered with it during the week. I'd pay for that convenience.


Since it's a bit more than a doubling of energy density, it's less that you can get a 500+ mile car and more that you can drop the price & weight of a 300-400 mile car. Imagine cutting the weight of an EV battery by 500 pounds while maintaining its current capacity. All that weight savings will probably get you some additional range, and save you on cost of materials, meaning you could cut the battery down a bit more to save even more on materials while saving a bit more weight. All told, you could have the exact same EV, but manufacturing the battery just got ~50% cheaper! That's what's exciting about this as a possibility, not 500+ mile cars.


I doubt range is increased much by reduced weight. Only rolling resistance is reduced, but most resistance at speed is from air resistance. Since energy is reclaimed from braking, the extra mass for acceleration is balanced by the extra mass for stopping, so it doesn’t help much with stop start traffic.

That’s how I mentally model it anyhow.


It's true that it's not a huge savings, but there's some savings. The EPA estimates approximately 1% reduction in fuel economy for each 100lbs added, so you might get a few % from the the battery weight savings.


Sure, for fuel economy, presumably without regenerative braking. When you're not in smooth traffic, a whole bunch of energy is lost in braking, and that energy is directly proportional to mass.


...provided the number of useful recharges is at least as high as Li-Ion, and preferably more like LiFePo or even better.


I think you'll find that for many people, EVs are a non-starter unless they can mimic the same travel timelines you can get from a combustion engine. 500 miles is very close to what they'd be looking for.


Also people who don't do all their driving in the city. That 250-mile battery shrinks a lot when your whole trip is at 80mph.


Plus it’s not always 70° in most places so the estimate is almost always optimistic to begin with


Yeah there's about three months of the year when I can set my AC to anything but maximum cold.


There are a lot of real world caveats that go into those range estimates. I just took my long range Tesla Model Y with an advertised 326 mile range on a multi-day road trip and I was stopping to charge about every 100 miles. I would love to get something with 3x the advertised range.


> I suspect that is a much smaller population than people tend to think.

Pickup truck owners will die on that hill.


Given an innovation of this sort, there is not a single area of application, extending the range of electric cars. You could also make lighter weight electric cars. Which would have their merits.

Think of the whole spectrum of EVs, lighter weight e-bikes, scooters, skateboards, or long range e-bikes. Electric aircraft start to become feasible.

Much more flight time out of your toy drone, multi-day battery life for your phone or laptop.

Energy storage in off grid setups becomes simpler, or more capacity in the same space.

Etc. etc.

All that provided this new design could function as a more or less slot in replacement, or better, for current lithium batteries in terms of manufacturing, cost, and what not.


Agreed on the small market, what would move the needle is if it re-charged much more quickly than current batteries.

EV owners really only want 500+ miles because charging the battery takes so long. Charging infrastructure is already changing and becoming more available so charging speed will be the real quest


Even if there is no demand for 500 mile range cars, solid state batteries are supposed to be twice the density of current batteries so a 3-400 mile car would still be something like 25% lighter than they would be with current batteries.


? Range is how often you need to recharge. For people like in apartments without home charging, this is huge, especially since homes are so unaffordable now.


More energy doesn't mean longer range for me. It means I can pass other cars and drive the speed I want when I'm up in the mountains, instead of having to eke out every last mile. If I get 8MPG in my mustang because I'm enjoying my drive, there are gas stations every few miles, even in state parks. EVs burn "gas" just as quick if you drive them the same way, but there's no charger for 60 miles. The KIA EV6 GT just can't make use of its 580hp in the places I'd like to enjoy it because it only has 200 mile range to start with.


Trucks, buses, planes, boats (eg ferries), smaller lighter cars, bikes, drones. Everything can benefit from smaller and lighter, or longer charge.


Americans don't buy cars anymore, though; not really. They buy ludicrous gigantic heavy pickups and SUVs. So what we're really talking about is getting decent range into oversized pickups that their owners want to accelerate like sports cars and still have a nice air-conditioned interior even when it's 150 degrees on the pavement due to climate change.


You can thank the EPA for that. The gov mandates that vehicles achieve a certain calculated efficiency, or there’s an extra fee/fine attached to the vehicle. Reasonable enough, right?

Unfortunately the way this is calculated is absolutely fucking retarded. Basically, the larger the wheelbase of vehicle, the lower fuel efficiency the vehicle can get away with.

This is why these fucking things keep ballooning in size, have a dogshit turning radius, and are causing an epidemic of frontovers and backover accidents killing or injuring thousands of children every year because there’s no up close visibility.

Video explanation: https://www.youtube.com/watch?v=azI3nqrHEXM

Old small trucks can actually command a premium because of this bullshit. Very few people actually like these huge stupid boats, but there’s just nothing else to buy when you need an actual work vehicle.

Please consider contacting your legislators and putting this on their radar, and keeping it there.


https://www.goodcarbadcar.net/2023-us-vehicle-sales-figures-...

The top 5 on that list are Ford F-series trucks by a large margin, followed by a Toyota small SUV and a Honda small SUV, before you get to the Toyota Camry, an actual car, followed by a Toyota truck.

Americans just really like their F150's!


Americans also buy a lot of small to medium CUVs


a solid sulfide electrolyte isn't necessarily fatal to claims of safety

i can't tell which sulfide it is from the nature link, but many metal sulfides release hydrogen sulfide only very slowly in contact with water, sometimes over geological timescales. it only becomes a problem if you, say, grind them up and mix the finely divided powder (which is also often pyrophoric!) into sheetrock

consider for example https://en.wikipedia.org/wiki/Chalcocite https://en.wikipedia.org/wiki/Covellite https://en.wikipedia.org/wiki/Pyrite https://en.wikipedia.org/wiki/Galena https://en.wikipedia.org/wiki/Sphalerite https://en.wikipedia.org/wiki/Mercury_sulfide https://en.wikipedia.org/wiki/Millerite https://en.wikipedia.org/wiki/Realgar https://en.wikipedia.org/wiki/Orpiment https://en.wikipedia.org/wiki/Stibnite and https://en.wikipedia.org/wiki/Molybdenite are all relatively stable metal sulfide minerals which don't offgas hydrogen sulfide fast enough to pose a significant hazard (or at all; many oxidize to sulfates instead)

even https://en.wikipedia.org/wiki/Calcium_sulfide is relatively innocuous aside from the bad smell, and https://en.wikipedia.org/wiki/Sodium_sulfide is routinely handled by photographers and dyers despite the hazard. you have to get into the exotics like https://en.wikipedia.org/wiki/Lithium_sulfide before metal sulfides really get scary


There are definitely a lot of lithium ions floating around, so lithium sulfide seems possible, as part of a failure cascade if nothing else.


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What is a "period of stability"? Sounds like a rather arbitrary and subjective designation, but it seems unlikely that an economy that has existed for thousands of years is yet to have its first "period of stability".


Right, exactly.

Did the Japanese print 80% of their money recently?




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