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For cars and trucks, current batteries are actually fine. Higher energy densities are mainly nice for things like high end sports cars where the form factor prevents cramming in more battery. But less so in freight trucks. Saving a few hundred kilos of mass on a truck that pulls 80 tonne is just not that valuable. It's nice but only if it doesn't raise the price too much. So what if you need a two tonne battery? The main constraint here is cost, not weight.
The aviation market on the other hand has an insatiable demand for high energy density storage. Hence companies like CATL announcing 500wh/kg batteries recently. That's double what you'd find in a high end car these days. And apparently they are working on even higher energy density batteries already.
Probably these are really expensive and hard to get. But it's going to add quite a bit of range to things like VTOL planes, drones, and other flying things that run on batteries. So, a NASA battery with high energy density and a few other nice properties (like needing no cooling/heating) could be worth the extra cost in this market. And better longevity means more time in between expensive overhauls as well.
From my understanding of the trucking industry, in many sectors, this isn't true at all. For example, in tipper trucks where you are carrying literal dirt and rocks from one place to another every kg counts and tare weight of the truck is very much a consideration, even in the relatively minor variations between diesel trucks.
In the US weight restrictions are even lower than in Europe in many states.
Given that road wear grows to the fourth power (!) with vehicle weight, I hope you guys feel well with the fact that your tax dollar subsidizes those ultra heavy trucks.
Divided by tire. That's why heavy trucks have so many of them.
Most countries regulate the weight by tire, so that this actually doesn't change between trucks.
On practice the impact of the truck is determined by law independently of the weight (on those superficial models, but there is also some depth where the regulation starts to fail).
Where can we find more on this? I'm not doubting, but I can't think of why this is. It's pretty rare to find much in the physical world that uses the 4th power (Hagen–Poiseuille equation relating fluid pressure differential in a pipe - or artery - is one of the few that comes to mind)
But this isn't really the right debate. Sure you need some last mile in many cases, but that's also often true with large trucks.
The simple fact is a far, far, far larger amount of transport could be handled by train if society put the right insensitive in place, rather then the completely backwards intensives that exist now.
In Switzerland its quite common for example to have even fresh food transported by train, the largest retailer works closely with the rail company and delivers to a number of regional depots where smaller (sometimes small or medium) trucks then take it to individual stores. We don't have these Wallmarkt supper stores that Americans (unfortunately for them prefer).
Its very common that larger stores, like Ikea actually are directly connected by the train network.
There could actually also be a lot more done to do cargo delivery by tram. This has started in a number of European cities. In Zürich the Cargo tram is currently mostly used for extraction of waste (like e-waste), not yet delivery, but it has potential.
Retail stores certainly existed before the automobile. People walked, biked or used horses to get to them. Horse and cart were used to deliver things to them.
Why haven't you told me earlier? I wouldn't have had to bother to walk to the supermarket across the street.
By contrast on American interstates the standard is 80,000lbs.
Your sarcasm is unwarranted and just makes you look stupid when you are completely wrong.
Weight savings are nice of course. But so is not burning diesel by the hundreds of gallons. The trade off is between a few percent extra weight or lots of dollars spent on fuel.
I know there are steep tariffs on Chinese EVs but I’m also wondering if these “cute little EVs” would pass US road safety tests. A disproportionate amount of weight in modern cars is safety equipment.
Also the most common car in Europe (Dacia Sandero), which is a 5-seater only weights 1 036kg. Gigantic American cars are a cultural phenomenon (which is mostly ad-driven by the way), it doesn't relate to an actual need.
Source for that? From this 2015 study[1], it doesn't seems to be the case at all in practice. (And maybe it the safety regulation has tightened up in the US since 2015, but the car size difference had already existed for at least the past 2 decades at this point). In any case, given the car fatality rate in the US compared to the EU[2], these regulation seem pretty ineffective (no amount of car safety can compensate for the very low driving skill in the US, caused by very lenient driving license requirements compared to European ones).
Also, I don't know how US safety rules apply but that would be pretty stupid if cars capped to 50km/h were subject to the same requirements as highway-ready cars.
[1]: https://spectrum.ieee.org/us-european-cars-show-safety-diffe...
I used to work in automotive assembly as a robotics engineer. Besides being well-known in the automotive industry, it doesn't take a lot of internet sleuthing to find.
"In general, there are two reasons why late-model cars are much heavier than their predecessors: safety and convenience."[1]
"The U.S. has a bunch of extra safety standards that the Europeans don't. For instance, in America, car makers have to design airbags to protect people who are not wearing their seatbelt. In Europe, they just assume that everyone's buckled up."[2]
I think you're conflating standards and the result of those standards with your links. You can levy a bunch of requirements that drive up weight and also don't have a meaningful impact on safety. We might even agree that they requirements aren't particularly effective, but that doesn't mean the manufacturers can skirt them. Whether or not the standards work, the result is the same: heavier vehicles.
>I don't know how US safety rules apply but that would be pretty stupid if cars capped to 50km/h were subject to the same requirements as highway-ready cars.
The market for those vehicles in the U.S. is extremely niche, generally relegated to ATVs. So much of the U.S. is connected by highways that there's very few people who a) want/need to own a car and b) also have no need to travel on the highways. People who only want a small urban commuter will often just get a scooter or motorcycle.
[1]https://www.jdpower.com/cars/shopping-guides/why-are-modern-....)
[2]https://www.npr.org/2015/10/16/449090584/why-arent-auto-safe...
Even if it's not mandatory, basically all cars have airbags in Europe nowadays, including tiny cars.
> [1]https://www.jdpower.com/cars/shopping-guides/why-are-modern-....)
Come on: “By law, modern vehicles are required to be fitted with a variety of safety-oriented technology (anti-lock brakes, stability control and tire-pressure-monitoring systems, etc.) and equipment (air bags,laminated glass, door intrusion beams, etc.)” not only these things are also mandatory in Europe, all the given examples aren't even heavy to begin with!
> The market for those vehicles in the U.S. is extremely niche, generally relegated to ATVs. So much of the U.S. is connected by highways that there's very few people who a) want/need to own a car and b) also have no need to travel on the highways. People who only want a small urban commuter will often just get a scooter or motorcycle.
Yet American only commute 20 miles per day on average (at an average 30mph). The fact that highways in cities are “technically highways” is only a cultural (and political) decision: the same kinds of roads in Europe are in fact not highways and speed is often limited to 70km/h for instance in France.
Anyway there are highway-ready cars (with airbags, ABS and all) that weight less than 900kg in Europe (Renault Twingo, Fiat 500, etc.).
Even if the cars all have airbags, it doesn’t mean they can pass US crash tests. That means they can’t nearly even be offered in the US. For example, EU frontal crash tests use a deformable barrier while the US does not. Relating to the study received for your safety assessment, it says the distribution of differences overlaps with zero. That’s a red flag that you can’t make a claim that they are any didn’t different.
Your claim about US commits is incorrect and less than half of the actual value in both distance and speed. Avg. speed is also not an appropriate metric.
I could go on, but there’s a lot to unpack. The latter point is that I’m not convinced you actually understand the differences between US or EU car manufacturing or parts of US culture that drive some of those decisions. There’s certainly an overrepresentation of SUV and trucks as commuter vehicles but there’s also a huge portion of the population, especially in the vast rural population, who have legitimate and pragmatic reasons to these vehicles. (And that’s coming from someone who drives a small hatchback)
Bruh, if you're gonna make statements like this, your argument needs to be stellar to back it up. And then you go:
> especially in the vast rural population
The US rural population is tiny, it's less than 20%, it's the same kind of argument as “people have families” when barely any household is more than 4 people.
The reason why almost 70% of people are driving an SUV or a truck has nothing to to with families (90% of which fit in a four-sitter) or the needs of rural life (that's also why pickup truck's bed has shrank so much over the past 5 decades). In fact, the growth in usage of these cars happened coincidentally to the decline of rural population and large families.
Your focus on safety as the root cause is also pretty dumb, since any SUV from the 90s would fail European current safety tests anyway, despite being enormous already.
> Your claim about US commits is incorrect and less than half of the actual value in both distance and speed.
Please provide your sources, because it doesn't match with what I could find online. (I realize that I made a calculation mistake: it's 20 miles and an hour in average so 20mph).
> Avg. speed is also not an appropriate metric.
Yes it is indeed. It's not perfect, but it's still appropriate, because it means that the commute time is driven by traffic congestion, and even your car going up to max speed for a small part of your trip isn't going to save you much time.
Well, for starters, did you actually look into the studies you cited or did you just take the first parts that confirmed your bias? For instance, the study that claimed European cars are safer in front/side crash tests admitted that the distribution of safety differences contains zero. It's important to understand the limitations of null-hypothesis testing. This means you can't discount that there is no actual difference between safety. This is why data literacy is important rather than just reading the abstract or conclusion and running with it.
>The US rural population is tiny, it's less than 20%
Again, this belies ignorance. Did you just grab the first Google result that confirmed your stance, or did you actually take time to understand the nuance? There is a massive disparity between what the census defines as rural vs. what is colloquially understood as rural. The census considers any population over 2500 people as an "urban cluster". That means US urban areas range from 2500-19.5MM. With that level of variance, you have to acknowledge large variance of “normal” use cases.
>Your focus on safety as the root cause is also pretty dumb
Please point to where I said it's the "root cause." I've only been advocating a more nuanced perspective. Also, see the HN guidelines for appropriate comments.
>Please provide your sources
The average round-trip commute as 55.2 minutes according to the US census and over 40 miles. Maybe you misspoke when you said "20 miles per day" and meant one-way?
>Yes it is indeed.
No, it's misguided and lacking nuance at best. Have you ever driven in southern California during rush hour? Your average speed is easily 30mph or less because you are essentially in a parking lot for huge periods. But that doesn't negate the need for a car to be able to reach highway speeds. Remember, the context was about safety of cars that are capped at 50km/hr, but now you're moving the goalposts and acknowledging the need for faster speeds just to maintain your position.
It's pretty clear you have your mind made up and prefer to argue rather than have a substantive and nuanced conversation.
Coming from the author of “you’re speaking from a place of ignorance” (+ other variations), I can only hope you're trolling at this point.
> This means you can't discount that there is no actual difference between safety. This is why data literacy is important rather than just reading the abstract or conclusion and running with it.
Given that the argument being refuted was “US cars are safer” the “no actual difference” case still counts as a refutation. How good is data literacy if you lack logical reasoning abilities…
> The census considers any population over 2500 people as an "urban cluster"
In an area were more than 2500 people live you'll most likely have actual roads and bridges, and don't need a truck to cross rivers or to drive on unpaved roads, so the definition is pretty much on point when we're talking about cars! And then 71% of the US population live in urban areas of more than 50k inhabitants so the smallest urban areas are in fact a small fraction of the total urban population (Edit: In any case, urban population living in areas with less than 10k is just 7M[1] so it's not these 2% of the US pop who make the car market either…). But yeah, I'm the one suffering from confirmation bias…
> Please point to where I said it's the "root cause."
Sure, here it is: https://news.ycombinator.com/item?id=37674080 you're welcome.
> But that doesn't negate the need for a car to be able to reach highway speeds.
Sure, one car able to go to highway speed for vacations and all. But must households don't need two of such cars!
> Remember, the context was about safety of cars that are capped at 50km/hr, but now you're moving the goalposts and acknowledging the need for faster speeds just to maintain your position.
Nope, the context is here: https://news.ycombinator.com/item?id=37658823 and I'm talking about both the Ami and the Sandero.
> It's pretty clear you have your mind made up and prefer to argue rather than have a substantive and nuanced conversation.
Cause you don't lack nuance at all ;).
[1]: https://www.federalregister.gov/documents/2022/12/29/2022-28...
There is no root cause claim there so you’re not saying much, other than strawmanning. If you look at a modern economy car, it weighs more than economy cars of the past or non-approved models for the US, despite using lighter weight materials for comparable components. So where does the extra weight come from? Mandatory safety features and options. That’s all the “disproportionate” statement is saying. It also wasn’t a comment to you, so a bit cringey that you try to search for any weak handhold to make your point.
You also picked a different comment to illustrate the context rather than your actual post, so I’m not sure your point. But it certainly lends credence to the idea of you moving the goalposts just to avoid being wrong.
I’ll give you more perspective since you missed the point. If the data contains zero it means it ranges from saying the US cars are safer to saying they are less safe. Zero is contained because it’s within this range. In other words, you can’t make strong claims at all. Again, data literacy is important.
> If you look at a modern economy car, it weighs more than economy cars of the past or non-approved models for the US, despite using lighter weight materials for comparable components. So where does the extra weight come from?
Ah yes, because your old car also had AC, electric window, and all the comfort a modern car has (including the car's form factor, giving more room for arms and legs, and less effort to get out of the car), and then the only difference must be safety…
> You also picked a different comment to illustrate the context rather than your actual post
Yes I took an adjacent comment in the same thread that you posted 5 minutes before your response to mine. So that must count as a completely different context, right? No, and you know it as well.
> If the data contains zero it means it ranges from saying the US cars are safer to saying they are less safe. Zero is contained because it’s within this range. In other words, you can’t make strong claims at all.
Of course you can make strong claims, and you're even making a strong claim yourself right now! The claim I make (which is ironically the same as the one you're making right now) is that the study shows that you can't make a strong claim about the US safety being higher than the one in the EU. Which was your argument!
Disagree. Car and truck makers try to optimize for grams and saving a kg of production vehicle is considered a huge engineering victory. Saving 100s of kg is a gigantic deal.
Weight is very very valuable on both passenger cars and commercial trucks. Hauling those extra 300-500kg vs a comparable size sedan comes at a steep cost too, as increasing weight requires stronger/wheels body, wheels, brakes, even engines.
There is a huge demand for higher energy density, preferably of a non-explosive kind.
As cost of the batteries comes down, these things will only become more popular.
Check: North American Council for Freight Efficiency (NACFE)
See:
https://electrek.co/2023/09/12/tesla-semi-proves-itself-fasc...
Not all data is out yet but the idea that electric trucks can drive useful range without anything but chips is complete nonsense.
The gigantic of track transports are blow 300 miles and a Tesla Semi can handle that under full load and difficult circumstances.
https://www.cnbc.com/2022/12/16/pepsico-is-using-36-tesla-se...
My car is at 150000 miles and it's still on the original set of brakepads. Some EVs actually have a problem with that, their brakes are used so infrequently that rotors start to rust. So automakers added firmware that periodically applies frictional brakes.
All I was trying to do is add some support to the claim that battery density does matter in cars (contrary to ancestor assertion). Less weight = less strain on brakes and tires = less nasties in the air and our lungs.
Standard Range Model 3: 1617
Long Range RWD Model 3: 1779
Long Range AWD Model 3: 1900
2022 Toyota Camry XLE: 1630
2021 Audi A6: 1970So you didn't read the article? The piece states: "Yi Cui’s team found an inexpensive nickel-molybdenum-cobalt alloy catalyst for the battery that costs $20/kg." For a catalyst, that doesn't sound too expensive.
> Their published research cites a $~83/kWh cost for just the materials (that's not very cheap)
That's all very nice, but that number is from a paper from 2018. And they state that it is the battery cost: "The estimated cost of the nickel-hydrogen battery reaches as low as ∼$83 per kilowatt-hour".
And pulling up 2018 data for LiIon, we get $~198/kWh.. (For instance, from here: https://about.bnef.com/blog/lithium-ion-battery-pack-prices-...)
Part of my critique is that the numbers cited in the article don't relate to their meaning. Measuring catalyst by kg instead of kWh is stupid, so $20/kg means jack when you look at what that actually means for a battery. Sounds hard to believe that there is an inexpensive anything made of only things like nickel-molybdenum-cobalt.
> That's all very nice, but that number is from a paper from 2018.
Hey I agree with you, but that's what the article cited. Maybe they shouldn't be citing a 2018 article. And I bet that $83/kWh was absolutely a best case estimate without manufacturing costs, nor accounting for scaling costs. Thats why I added the link for context.
I think LFP is basically already under that as well (I think they are in the 60-70/kwhr range).
For grid storage, that is probably the only metric that matters: cost per kwhr of storage (and sufficient cycle endurance).