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Vertically aligned carbon nanotubes triple the density of lithium batteries

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Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#71

Post by analognoise »

datameta wrote: post #62
analognoise wrote: post #51

Earlier quoted context omitted.

You can fit an entire Italian town in the size of a freeway interchange in Houston: https://www.texasmonthly.com/politics/highway-interchange-ho... Our cities were designed to be spread out to make them less susceptible to atomic weapons in the 1950's (not a joke). So... Yes, we need cars. It really is a long way for many of us.

Granted, not to take away from the point of different use cases, however Sienna is a very small medieval-era town that one can walk across at leisure and the Houston interchange is one of the most complex in the US. So it is somewhat of a hyperbolic comparison. I agree that very common suburban and rural vehicles, respectively, are SUVs and pickup trucks. But I am curious what portion of urban drivers use a vehicle t…

Why would you want a vehicle that only covered 95% of your use cases?

It's like condoms - better to have it and not need it than need it and not have it.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#72

Post by baq »

choeger wrote: post #53
DennisP wrote: post #34

Earlier quoted context omitted.

Electric airplanes need significantly better energy density.

I don't know. Sure, if you can build batteries with the energy density of gasoline, you can build an electric plane with them. But is this really necessary ? Right now, we have relatively large, relatively fast, jet planes. Do we need that size and that speed to be commercially viable? Could we also run a larger fleet of smaller, more automated planes or helicopters? If there was no kerosene left by tomorrow morning,…

the problem with jets is stratospheric water vapor in addition to all the CO2 they emit (quite a lot in itself).

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#73

Post by NeutronStar »

[deleted] wrote: post #64
_fizz_buzz_ wrote: post #55

Earlier quoted context omitted.

It's probably going to be like with AI. People talk about it for years and nothing substantial happens and then suddenly it takes off. I was working on AI around 2005 (we called it neural networks). There were no good libraries, the literature was difficult to understand and nothing really worked (at least I didn't get it to work). I was still a student and pretty disillusioned by the whole idea. A few years later th…

[deleted]

Ahh yes, your wife's 3 letter name pronunciation is the penultimate AI test.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#74

Post by lopmotr »

danmaz74 wrote: post #19

Actually good article if you continue reading. Comment from an independent expert: "Research has shown vertically aligned – or even just well distributed – carbon nanotubes have far greater properties than randomly placed carbon nanotubes," said Dr. Shearer. "I am not surprised a x10 in conductivity is possible. Controlling the placement of carbon nanotubes is really the way to unlock their potential. The issue in co…

Even if it was 10x the cost, it's supposed to last 5x as long so long-lived applications like perhaps commercial vehicles would only be 2x the cost even if they don't take advantage of the smaller size & weight to require less capacity.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#75

Post by Retric »

0xffff2 wrote: post #57
DennisP wrote: post #34

Earlier quoted context omitted.

Electric airplanes need significantly better energy density.

"significantly" sells it short. Electric airliners need a couple orders of magnitude of improvement to even come close to viability.

Jet engines are significantly less efficient than electric engines so it’s lithium ion has 1/20th the useful Specific Energy at takeoff, though that gets worse as the flight progresses and fuel is burned or batteries age. On the other hand for ultra long range flights electric jets can cruise as higher altitudes which makes up for some of that. Also having 1/3 the 15,000 km range of some aircraft is perfectly viable.

IMO, Due to cost savings electric aircraft would likely become common at around 4x the current Specific Energy and fully take over at about 10-20x.

PS: Energy density is fine for lithium ion, the issue is energy per weight (Specific Energy) not energy per volume (Energy Density).

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#76

Post by baq »

x86_64Ubuntu wrote: post #59
_fizz_buzz_ wrote: post #55

Earlier quoted context omitted.

It's probably going to be like with AI. People talk about it for years and nothing substantial happens and then suddenly it takes off. I was working on AI around 2005 (we called it neural networks). There were no good libraries, the literature was difficult to understand and nothing really worked (at least I didn't get it to work). I was still a student and pretty disillusioned by the whole idea. A few years later th…

I don't know, it seems like AI/ML are on the cusp of the "Trough of Disillusionment" themselves. And they've been talking about Graphene, Nano-tech since I was in high school.

it just stopped being AI. night mode camera on recent android and iphones were top of the line AI couple years ago. DLSS (deep learning super sampling) is allegedly borderline magic; it'll just be DLSS sometime next year. google translate and alpha zero are most definitely amazing AI.

carbon nanotubes? yeah.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#77

Post by driverdan »

rocqua wrote: post #6

IF this is true, it would be a massive breakthrough. Truly monumental. Hence, I am skeptical. But otherwise, this would be a massive thing. a 2x capacity per weight advantage of batteries? Without an increase in space? That comes down to doubling the range of EVs, and making electric planes and rockets a lot more viable. A 3x capacity per space advantage means roughly a 3x improvement in your phone and laptop battery…

> A 10x speedup of charging?

Not possible with existing infrastructure. The limiting factors are cooling the batteries and feeding them enough power. On small scale like laptops it's possible to speed up charging but not at large scale like cars.

That isn't to say it may be possible in the future but it isn't now.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#78

Post by pjc50 »

choeger wrote: post #53
DennisP wrote: post #34

Earlier quoted context omitted.

Electric airplanes need significantly better energy density.

I don't know. Sure, if you can build batteries with the energy density of gasoline, you can build an electric plane with them. But is this really necessary ? Right now, we have relatively large, relatively fast, jet planes. Do we need that size and that speed to be commercially viable? Could we also run a larger fleet of smaller, more automated planes or helicopters? If there was no kerosene left by tomorrow morning,…

> If there was no kerosene left by tomorrow morning

I suspect the medium term solution would be to make some, either from other hydrocarbons or plant cellulose, or even by the US Navy seawater CO2 to liquid fuel process.

Re: Vertically aligned carbon nanotubes triple the density of lithium batteries

#79

Post by seanc »

0xffff2 wrote: post #58
pbhjpbhj wrote: post #35

Earlier quoted context omitted.

>Or, more likely, a slight improvement in your phone and much thinner phones. On laptops, we might see the return of more ports. // Please, no. I don't understand the utility of making something so expensive be so fragile and hard to hold. My phone is 5mm thick, that's already too thin for me. Does anyone want thinner phones or is it just a marketing thing?

The thinner the phone, the thicker the case I can put on it with the same total thickness. It's incredibly rare to see a case-less phone in the wild these days.

I heard somewhere that in Holland every bicycle + lock weighs 5kg. If you have a cheap 5kg bike no one wants it and you don't have to lock it. If you have an expensive 1.5kg bike you need a lock that weighs 3.5kg to protect it.
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