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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#551

Post by danudey »

derefr wrote: post #453
armarr wrote: post #446

Earlier quoted context omitted.

Sure, it would make the wiring smaller and more efficient. But I also don't see how it would help in the chemical energy transfer to charge the battery.

What I was trying to say is, with some battery chemistries, the current (heh) limiting step for charging speed is the wiring into, and of, the battery, rather than the safe reaction speed of the battery chemistry itself. We could safely "crank the chemistry" by an order-of-magnitude or more if we could get the desired current into the battery without the wires+electrodes conducting undue amounts of heat into the elec…

According to the paper, this material stops superconducting at about 150mA per cm^2 of diameter, meaning that a 1cm-thick cable made of this material could conduct up to 150mA before the current is too much and it stops superconducting.

If my math is correct, then for a basic 500mA USB device, that would mean a cable a bit over 3 cm^2 in cross-sectional area, or about 2 cm across (for each of the power and ground leads, at least).

Alternately, a cable of just over 1/2cm in diameter (for power and ground, each) could charge a rechargable Ni-MH AA battery in about 12 hours and 40 minutes.

Tl;DR this is absolutely revolutionary science, if true, but we're definitely Not There Yet.

Re: A room-temperature superconductor? New developments

#552

Post by jacquesm »

civilitty wrote: post #541
jrockway wrote: post #537

Earlier quoted context omitted.

Are you thinking of supercapacitors?

He's thinking of superconducting magnetic energy storage: https://en.wikipedia.org/wiki/Superconducting_magnetic_energ... Currently they're only feasible as high quality power sources for fabs and other industrial uses because of the operating costs of cooling the superconductors.

Also used for grid stabilization.

Re: A room-temperature superconductor? New developments

#553

Post by danudey »

zepearl wrote: post #487
jtchang wrote: post #418

The ramifications of the inflection point we are currently at is mind boggling. I had a hard time explaining this last night but we may very well be witnessing the beginnings of a technological transformation era much like when the p-n junction was invented. From the 1940s standpoint it would be hard to envision all we had today. - Lossless transport of energy - Batteries that don't take any time to recharge - Faster…

> Can I have my flying car now? Let's not forget the flying skateboard of the film "Back to the future". I loved it in the film and it's a dream that I still have today - I'm now almost 50 years old so I would probably crash and get killed by using it, but I would still give it a try :)

There's no need to wait for flying skateboards, you can buy a regular skateboard at any shop around town and crash and get killed by using it.

(Said in jest by someone who recently turned 41 and hurt his back playing video games last year)

Re: A room-temperature superconductor? New developments

#554

Post by GMoromisato »

netrus wrote: post #502
GMoromisato wrote: post #426

Earlier quoted context omitted.

I always call this a "local maximum" problem. Once you've optimized the crap out of your tech, any change makes it worse (e.g., replacing crossbows with primitive guns). But if you do switch, then optimizing that technology takes you to an even higher maximum. The problem is that you have to go backwards to go forwards, and you can't always predict (or convince the powers-that-be) that the end result will be better.

Extremely relevant to electric cars. Looks like we are close to electric > ICE, (or past that point, whatever), but it was a long painful time of hyping subpar cars by those who believed in the potential of the technology.

Agreed! I also believe that once we flip (EV > ICE) the momentum goes the other way.

For example, let's say that 50% of cars on the road are EVs. Now gas stations have a problem. You can't survive with half your customers gone, so maybe half the gas stations go out of business. But that means your nearest gas station is much further away, so now the incentive for EV goes up.

In California (and the Bay Area, particularly), I bet we'll see this relatively soon.

Re: A room-temperature superconductor? New developments

#555

Post by mitthrowaway2 »

distortionfield wrote: post #425
zamadatix wrote: post #242

Earlier quoted context omitted.

A room temperature and pressure semiconductor is more an astoundingly large jump forward in the space than something that defies known physics.

That doesn’t track. The EmDrive was legitimately pushing a premise that we had some fundamental law of physics wrong. Superconductors are pretty well understood, they’ve been around for a while. Finding a room temperature one isn’t that big of a jump, it’s just a really hard one to make.

You're in agreement with the GP, their comment was just hard to parse.

Re: A room-temperature superconductor? New developments

#556

Post by nextaccountic »

fsh wrote: post #516
jtchang wrote: post #418

The ramifications of the inflection point we are currently at is mind boggling. I had a hard time explaining this last night but we may very well be witnessing the beginnings of a technological transformation era much like when the p-n junction was invented. From the 1940s standpoint it would be hard to envision all we had today. - Lossless transport of energy - Batteries that don't take any time to recharge - Faster…

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

> CPU heat output is limited by the resistance of the semiconductors.

Can't superconductor help here?

Re: A room-temperature superconductor? New developments

#557

Post by jacquesm »

highwaylights wrote: post #521
derefr wrote: post #451

Earlier quoted context omitted.

Depends. A single battery cell would have nontrivial resistance, yes. But a big bank of batteries, like are in an EV? Very hard to give them enough current to heat them up. Most of the "heat problem" is from the bottlenecked current path into the car; once you fan out across all the individual cells, each individual cell isn't receiving much current. And a bank of supercapacitors? You could charge it effectively inst…

Additionally you need to have the current to deliver in the first place. Having a grid that can dump 25-100 kwh into any given car in a couple of minutes is no small task if everyone is doing it.

The utilization factor would obviously be much lower than it would be if everybody charges at a lower rate so if the total amount of energy is equal that just means that individual vehicles will spend less time charging, and the grid will see - roughly - identical utilization on average but the peaks may be higher.

Re: A room-temperature superconductor? New developments

#558

Post by fragmede »

Workaccount2 wrote: post #304
orangepurple wrote: post #249

Earlier quoted context omitted.

China has more people, more money to spend on research, more equipment, more access to raw materials and chemicals, more manufacturing base, more STEM graduates, more everything, and all of that by huge margins. USA scientists will eventually put something out, but 10x more slowly than China.

All the smart people in the US work in tech and finance. If you have a big ole' brain, why would you take $80k to work in some crumby lab when you can get paid $350k to maintain a login screen from the comfort of your mountain side home.

Because there's more to life than money. For King and Country.

Re: A room-temperature superconductor? New developments

#559

Post by mitthrowaway2 »

emtel wrote: post #508
lolinder wrote: post #412

Earlier quoted context omitted.

So why is everyone getting so excited about superconductors when all we actually know is this (probably) exhibits diamagnetism? Is diamagnetism super rare outside of superconductors?

It's rare for it to be strong, from what i've seen. Based on the videos that have been shown, it appears that it would be the most strongly diamagnetic substance (other than superconductors) known by a wide margin. In comparison, levitating things like pyrolytic graphite seems to require truly massive magnets to achieve even millimeters of levitation: https://www.youtube.com/watch?v=VC3r9-OaWes

And part of the reason that succeeds is because graphite is very light. A chunk of LK-99 is three times as dense, so getting it to levitate is extremely impressive even if it's just conventional diamagnetism.

Re: A room-temperature superconductor? New developments

#560

Post by bugglebeetle »

baja_blast wrote: post #112
bugglebeetle wrote: post #45

With all the recent “the government has alien spacecraft news” and the bizarre circumstances of this material’s creation, the (I know to be ridiculous) conspiratorial part of my mind is going “I guess climate change is finally forcing them to take stuff out of the extraterrestrial vaults.”

I don't know, the material is a ceramic made of a powdered lead, copper, sulphur, phosphorus and oxygen heated up together. It's not some advanced meta material which if true it's amazing this was not discovered earlier but let's just hope it is.

This was intended as a joke, but since most raw materials in the universe are the same, extraterrestrials deriving novel combinations is just as, if not more likely, than meta materials etc.
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