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Nickel Hydrogen Batteries by NASA

spectrum.ieee.org

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Re: Nickel Hydrogen Batteries by NASA

#81

Post by bumby »

jillesvangurp wrote: post #31
dabeeeenster wrote: post #9

Earlier quoted context omitted.

EVs do 100% need to get lighter. They are still quite a bit heavier than their ICE equivalents and tyre wear is (IMO) underappreciated as a toxin/pollutant.

There are quite a few lighter EVs. Including some classic car conversions that actually manage to be faster and lighter than their originals. Those cute little EVs that are mass produced in China are far lighter than the super sized trucks people in the US drive. And of course any muscle car burns out its tires, brakes, and has terrible fuel economy.

>Those cute little EVs that are mass produced in China are far lighter than the super sized trucks people in the US drive.

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.

Re: Nickel Hydrogen Batteries by NASA

#82

Post by bumby »

littlestymaar wrote: post #48
ilyt wrote: post #41

Earlier quoted context omitted.

Most people buy neither small EVs (they have family) nor musclecars (they, again, have family)

You definitely don't need a 3t truck to carry your family, especially when you know how small modern families are… The average household size in the US is 2.53. And 63% of households are only made of one or two person (that is, the majority actually doesn't “have a family”), which fits in 482 kg Citroën Ami. Also the most common car in Europe (Dacia Sandero), which is a 5-seater only weights 1 036kg. Gigantic America…

I’m not discounting the cultural part because it’s a big factor, but you’re also missing that the US has more stringent safety standards that significantly drive up weight. There’s more reasons that those little Opals and Citroëns aren’t sold in the US beyond cultural norms.

Re: Nickel Hydrogen Batteries by NASA

#83

Post by liftm »

thfuran wrote: post #60
soco wrote: post #19

Earlier quoted context omitted.

How are today's batteries doing when put in the barbecue fire? The new ones only need to not do (much) worse.

How batteries do when placed in a barbecue is, for most applications, much less important than how often they spontaneously initiate a barbecue.

I laughed, but is that really true? You're going to have a lot of batteries/cells in one place, and one will inevitably start barbecue. Isn't the question whether the rest joins?

Re: Nickel Hydrogen Batteries by NASA

#84

Post by thfuran »

liftm wrote: post #83
thfuran wrote: post #60

Earlier quoted context omitted.

How batteries do when placed in a barbecue is, for most applications, much less important than how often they spontaneously initiate a barbecue.

I laughed, but is that really true? You're going to have a lot of batteries/cells in one place, and one will inevitably start barbecue. Isn't the question whether the rest joins?

I suppose it is probably hard to engineer a battery that is prone to spontaneous barbecues but resistant to the influence of outside barbecues. But I'm not sure I agree that it's just a numbers game that if you put enough of something in one spot, some of them are bound to suddenly catch fire without outside intervention.

Re: Nickel Hydrogen Batteries by NASA

#85

Post by littlestymaar »

bumby wrote: post #82
littlestymaar wrote: post #48

Earlier quoted context omitted.

You definitely don't need a 3t truck to carry your family, especially when you know how small modern families are… The average household size in the US is 2.53. And 63% of households are only made of one or two person (that is, the majority actually doesn't “have a family”), which fits in 482 kg Citroën Ami. Also the most common car in Europe (Dacia Sandero), which is a 5-seater only weights 1 036kg. Gigantic America…

I’m not discounting the cultural part because it’s a big factor, but you’re also missing that the US has more stringent safety standards that significantly drive up weight. There’s more reasons that those little Opals and Citroëns aren’t sold in the US beyond cultural norms.

> but you’re also missing that the US has more stringent safety standards that significantly drive up weight.

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...

[2]: https://data.oecd.org/transport/road-accidents.htm

Re: Nickel Hydrogen Batteries by NASA

#86

Post by bumby »

littlestymaar wrote: post #85
bumby wrote: post #82

Earlier quoted context omitted.

I’m not discounting the cultural part because it’s a big factor, but you’re also missing that the US has more stringent safety standards that significantly drive up weight. There’s more reasons that those little Opals and Citroëns aren’t sold in the US beyond cultural norms.

> but you’re also missing that the US has more stringent safety standards that significantly drive up weight. 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 t…

>Source for that?

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...

Re: Nickel Hydrogen Batteries by NASA

#87

Post by selimthegrim »

AtlasBarfed wrote: post #4
scott_h wrote: post #2

[dead]

CATL's sodium ion batteries are slated to soon (1-2 years, mostly just mundane factory construction and logistics) to hit $40/kwhr. No nickel / cobalt / etc. 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).

Factory might not be a done deal - https://news.ycombinator.com/item?id=37677943

Re: Nickel Hydrogen Batteries by NASA

#88

Post by panick21_ »

VBprogrammer wrote: post #29
onlyrealcuzzo wrote: post #27

Earlier quoted context omitted.

Ah, yes, because trains clearly could not do this and never did in the past. There is no alternative.

Trains have never delivered to individual retail stores, half finished housing estates or petrol stations. Perhaps reserve your sarcasm for when you aren't saying something stupid.

This is not totally true. It was very common to have markets right next or even under train stations. It was also common for trains to do milk delivery with stores close to rail stations. You also had trains going threw cities on street levels to unload.

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.

Re: Nickel Hydrogen Batteries by NASA

#89

Post by panick21_ »

jojobas wrote: post #67
jillesvangurp wrote: post #36

Earlier quoted context omitted.

Nonsense. There are battery electric trucks in every vehicle class you can name. 200 tonne road trains in Australia, check. Mining trucks, check. Not a problem. There are also multiple electrical class 8 semi's on the road already. Tesla class 8 semis is a good example. But you can also get similar trucks from e.g. Volvo. Long distances buses, school buses, vans, etc. All available right now. As cost of the batteries…

Yeah, check what range Pepsi is getting hauling anything but Lay's.

Complete nonsense.

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.

Re: Nickel Hydrogen Batteries by NASA

#90

Post by marcosdumay »

bumby wrote: post #80
marcosdumay wrote: post #56

Earlier quoted context omitted.

> fourth power (!) with vehicle weight 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.

Regulated by tire or by axle? In the US, it’s generally the latter.

Yes, by writing it by axle on the regulation is common. There is also a requirement for a minimum number of operating tires in an axle. (I don't keep close track of this, but I don't think it's always 2.) And requirements for tire pressure (that changes how much damage the truck causes too).

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).

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