typodupeerror

## Step Toward Liberating Electronic Devices From Their Power Cords130

Posted by Unknown Lamer
from the supercapacitive-cats dept.
Science_afficionado (932920) writes "A new type of supercapacitor that can hold a charge when it takes a lickin' has been developed by engineers at Vanderbilt University. It is the first 'multi-functional' energy storage device that can operate while subject to realistic static and dynamic loads — advancing the day when everything from cell phones to electric vehicles will no longer need separate batteries. These devices could make it possible to design electrical devices that are not limited by plugs and external power sources."
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## Step Toward Liberating Electronic Devices From Their Power Cords

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• #### I hate it when; (Score:1, Troll)

A supposedly intelligent author feels the need to say "ten times less"
• #### Re: (Score:3)

"Ten times more" would mean multiply by ten, so it makes sense that "ten times less" means divide. It's consistent, and that's the main thing.
• #### Re: (Score:2)

"Ten times more" would mean multiply by ten, so it makes sense that "ten times less" means divide. It's consistent, and that's the main thing.

If 10=more and 5=less, which is greater, 10 times less or 11 times less?

• #### Re: (Score:2)

That's like saying if 10=more and 5=less, which is greater, one tenth, or one eleventh.
• #### Re: (Score:2)

No. Saying 10 times less implies less has a value. If less has no value, then 10 times less = 0.

Its not a matter of knowing what the author meant. Its simply a matter of correctness. Don't submit anything to a science journal or a legal entity, and you'll be just fine.
• #### Re: (Score:2)

Would you be happier with "ten times lower" or "ten times lesser" at least?
• #### Re: (Score:2)

No, i"d be happy with the correct, "one tenth", or "a tenth", or "10 percent of", or any other grammatically and mathematically correct way of saying it.
• #### Re: (Score:2)

Well then there's nothing more I can really say apart from: The author's way of using "less" I think is fine. Language evolves all the time, and I think this usage is not only perfectly acceptable, but is consistent, and even an *improvement* in many cases (since for other numbers, it's potentially awkward - see my other post [slashdot.org]).

As someone else pointed out, it's even MORE appropriate given what he said in the sentence: “Supercapacitors store ten times less energy than current lithium-ion batteries, b
• #### Re: (Score:2)

As someone else pointed out, it's even MORE appropriate given what he said in the sentence: “Supercapacitors store ten times less energy than current lithium-ion batteries, but they can last a thousand times longer.". That's a good way to contrast 10 with 1000, and it's said eloquently, making perfect sense to probably 99.9% of the population.

There are two problems with that theory. First, the storage capacity and the duration aren't actually comparable numbers. Second, if they were, you'd want to be comparing them at a factor of 10,000 - if the original sentence leads you to "contrast 10 with 1000," as you say then its poorly constructed. Contrasting "One tenth with one thousand," or "0.1 with 1,000" written numerically, would actually be the correct goal of the sentence.

All of that ignores the fact that the storage capacity varies with size

• #### Re: (Score:2)

Ten times more would be x + 10x = 11x. Ten times as much would be 10x.
• #### Re: (Score:2)

Hmmm... how about "ten times greater" or "ten times higher"? Would you be happier with "ten times lesser" or "ten times lower" then?
• #### Re: (Score:2)

By saying X times "more" or "less", the "more" or "less" or "greater" or "lesser" the writer adding is a qualitative assessment and not a mathematically significant descriptor. The correct way to write it "10 times" or "one tenth", any increase or decrease is obvious to anyone with a grade-school education and consistent for mathematically experienced readers. Alternately, if the author wants to state the obvious they can say "increased to 10 times" or "reduced to one tenth". Journalist used to write lik

• #### Re: (Score:2)

Consistent? Not really. What if someone writes "0.1 times less". Strictly speaking, X times 0.1 is one tenth of X and would be the correct interpretation. But modern vernacular, the "less" indicating division, it would be X divided by 0.1 equaling 10X.

On a side note, what ever happened to teaching journalism students basic math?

• #### Re: (Score:2)

Since it's not a scientific paper, but an article for the general public, "0.1 times less" would never get printed, is not in common usage, and so is technically undefined as of yet, but I see your point.

The point is, even amongst those who are compaining, I bet not ONE slashdotter misinterpreted that sentence in the original article.
• #### Re: (Score:2)

In addition to it being completely unambiguous (unless you argue that caps can store negative energy), the line in question is not technical writing, but a verbatim quotation. The maligned author isn't even responsible for the sloppy terminology, the quoted speaker is.

• #### Re: (Score:2)

Ten times is a multiplication, more is add, less is subtract.

Ten times more is c+10*x

Ten times less is c-10*x

A tenth of is x/10

A tenth less is x-x/10

Nine tenths less is x-(9*x/10)

So your saying that ten times less is the same as nine tenths less.

Ain't nobody got time for that.

• #### Correction (Score:2)

x+10*x and x-10*x in the first two formulas.

And "you're", not your. Ouch.

Me too!!!!

• #### How would this get rid of power cords? (Score:5, Insightful)

on Wednesday May 21, 2014 @08:03AM (#47055329)
As far as I understand, in practice using a supercap isn't much different from using a battery. The energy density might be different but it's not like they magically create energy from thin air. They still need to be charged. Or are we talking energy densities that would last for the entire life of a device here?
• #### Re:How would this get rid of power cords? (Score:5, Interesting)

on Wednesday May 21, 2014 @08:21AM (#47055459) Homepage

My cell phone needs charged at night, but I don't consider it to be a wired phone and I don't find the charging cord to hinder me when making calls. My laptop, on the other hand, stays plugged in most of the time because it won't last a full day otherwise. It is hampered by the power supply.

I think the idea here is that short term charging for devices is necessary, but normal operation would be wire free, thus they are liberated from wires.

• #### Re:How would this get rid of power cords? (Score:5, Informative)

on Wednesday May 21, 2014 @08:37AM (#47055591) Homepage
We are pretty much getting to this point without the help of super capacitors. With new batteries, solid state drives, and low power (not low speed) chips, it's possible to make a laptop last 20 hours [laptopmag.com]. It's not mainstream, but give it another 2 or 3 years and it won't be uncommon that you'll only have to plug in you laptop at night, just like you do with your phone.
• #### Re: (Score:2)

I still get 6-7 hours out of a 15" retina MBP used for development; add an extra 1/8" of thickness worth of battery and we'd be there now (although it wouldn't be as fun to carry around).

• #### Re: (Score:2)

What kind of a workload are you looking at on the go? For office/web/coding, there are many laptops already available that will last longer than your typical smartphone.

I have a Thinkpad X220 (Sandy Bridge) that I unplug in the morning, use on battery all day (9 cell 94Wh) and then plug in when I get home, usually with 20-30% remaining after an active runtime of roughly 10 hours. A 13" MacBook Air should be able to improve on that time...

• #### Re:How would this get rid of power cords? (Score:5, Informative)

on Wednesday May 21, 2014 @08:29AM (#47055511)
The supercaps would be more like permanent batteries, and could be implemented in applications where retrieving a dead battery is inefficient.

This is potentially groundbreaking. Current battery tech leaves a lot to be desired, the materials being used are finite, and it's possible there are no more great leaps in efficiency using chemicals to store energy.

This is an entirely different way to store energy and the tech is in its infancy... storage capacities will likely improve with research.

• #### Re: (Score:3)

Yea, but you still have to charge it. There's still a cord. The summary of both the article and the summary are basically an outright lie. The energy density is still less than that of a battery, and the tensile strength is ok... but not that great. Your device wont weigh any less, it just might be a bit smaller or have more room for other features because the battery is the case or components.

A more honest headline would have been: "Electronic devices may soon be smaller and charge faster!"
There's nothing

• #### Re: (Score:2)

A more honest headline would have been: "Electronic devices may soon be smaller and charge faster!" There's nothing in this technology that will eliminate the need for a cord.

Another equally honest headline would have been "Electronic devices may soon hold much more charge allowing them to be used without frequent charging via power cords or where existing battery powered devices would be impractical". The existing headline suggests the same thing with nineteen fewer words.

• #### Re: (Score:3)

Another equally honest headline would have been "Electronic devices may soon hold much more charge allowing them to be used without frequent charging via power cords or where existing battery powered devices would be impractical". The existing headline suggests the same thing with nineteen fewer words.

I don't buy it. Take a cell phone for example... the existing lion batteries have more mass than the phone chassis, and they have 10 times the energy density of the supercap in question. Just for the sake of argument, let's say the phone chassis has twice the mass of the existing battery, and lets say you replace both the battery and the phone chassis with this supercap material. You would end up with 3/10ths the energy capacity.

AFAICT, this tech does nothing to eliminate power cords. Even in their example

• #### Re:How would this get rid of power cords? (Score:5, Insightful)

on Wednesday May 21, 2014 @08:39AM (#47055603)

The summary (and the article, to an extent) is bad; this is a supercapacitor that also serves as a structural part, so all sorts of random things can be turned into (weak) batteries.

They're envisioning a world where buildings, cars, and all sorts of things could be turned into giant capacitors, and you could just pump energy in somewhere and then draw it out wherever you like using some kind of short-range wireless transfer.

The idea is a bit half-baked, but I support any science that makes our world more like Star Trek, even if it takes the form of mundane objects randomly exploding when there is a power surge.

• #### Re: (Score:3)

The summary (and the article, to an extent) is bad

In case you're on a browser thats removed the URL bar: This is slashdot.

• #### Re: (Score:2)

A building out of supercapacitors? I guess that could be interesting in a thunderstorm...
• #### Re: (Score:2)

I wonder how many of these supercapacitors you could charge with a lightning strike.
• #### Re: (Score:2)

If they want to turn everything into big capacitors, I hope they work in ways to keep you from accidentally discharging it (years ago I took apart a cheap point-and-shoot camera and I touched the capacitor for the built-in flash and got quite a nice shock).
• #### Re: (Score:2)

where buildings, cars, and all sorts of things could be turned into giant capacitors

Having been shocked by a large cap back when I was fiddling around with discrete electronics back in the Dark Ages, the notion of being inside a building-sized cap thrills me so much that I think I'll be sick that day.

Seriously, a building-sized cap failing spectacularly would not be a fun thing to be near.

• #### Re: (Score:2)

That explains Star Trek objects exploding all the time.
• #### Re: (Score:2)

That explains Star Trek objects exploding all the time.

Probably nothing will ever actually successfully explain why so much stuff on the bridge explodes all the time. The bridge should be isolated from the rest of the ship, with some kind of extremely nonconductive isolation technology used if necessary, plastic pushrods or whatever.

• #### Re: (Score:1)

Don't take it literally, the power cords would still be there but since supercapacitors charge in minutes, not hours, you wouldn't have to stay connected all the time to recharge, thus "liberating" you from the power cord.
• #### Re: (Score:2)

Though replaceable batteries provide much the same benefit.

• #### instant charge. Touch, not plug in (Score:2)

Capacitors charge virtually instantly, so a device wouldn't have a power cord attached to it for hours. Instead, you'd just touch it to the charger.

• #### "not limited by plugs and external power sources" (Score:3, Insightful)

<gaygirlie@hotmaiLIONl.com minus cat> on Wednesday May 21, 2014 @08:03AM (#47055335) Homepage

Bullshit. Where exactly do they plan to get the power to charge those supercaps? From thin air?

• #### Re: (Score:2)

TFS is misleading.

One of the great advantages of this new tech is the super capacitor can be charged and discharged for millions of cycles, versus thousands of cycles for existing battery technology.

• #### Re:"not limited by plugs and external power source (Score:5, Informative)

on Wednesday May 21, 2014 @08:30AM (#47055523)
The other advantage is the speed at which you can charge a capacitor compared to a battery. I have a consumer cordless screwdriver with a capacitor in place of a battery. It runs for a decent time and runs down, like most such devices. Unlike a battery, it recharges to full in 90 seconds, not hours.
• #### Re: (Score:2)

I have a consumer cordless screwdriver with a capacitor in place of a battery. It runs for a decent time and runs down, like most such devices. Unlike a battery, it recharges to full in 90 seconds, not hours.

Link please? That sounds like something worth buying...

• #### Re:"not limited by plugs and external power source (Score:5, Insightful)

<allsquiet@hotmai[ ]om ['l.c' in gap]> on Wednesday May 21, 2014 @08:41AM (#47055629) Journal

TFS is misleading.

One of the great advantages of this new tech is the super capacitor can be charged and discharged for millions of cycles, versus thousands of cycles for existing battery technology.

Actually, that's not really the point of the article, either. Large numbers of charge-discharge cycles are a feature of pretty much any supercapacitor, not just these ones. They're arguing that these new supercapacitors have sufficient mechanical strength and robustness that that could be used as structural, load-bearing components in some applications. In other words, you don't have to put a box around them; they can be an integral part of the frame or case of your device. The battery (or capacitor) doesn't have to be a separate, discrete, armored lump inside the case.

In practice, as long as the energy storage density of these things is still just a tenth that of rechargeable lithium ion batteries, they're going to have problems in mobile applications. Near-indestructible material and near-instantaneous charging are both good things. But I'm not really "liberated from my power cord" if I have to top up the capacitor every couple of hours, or if my new battery-less iPhone weighs a couple of pounds with its giant supercapacitor frame.

• #### Re: (Score:2)

Supercaps also charge a lot faster, because they don't have to convert the charge to a chemical change like a battery. But they are also very touchy devices, and you especially don't want to go over their voltage rating. It's the same reason you want to specify double the voltage rating for electrolytic caps.
• #### Re: (Score:3)

Electrolytic voltage ratings are somewhat meaningless. They specify one of infinite meaningful measurements for the same thing.

A 50V capacitor isn't just 50V; it's 50V rated for some operating hours. Let's say 10,000 hours. If your capacitor oscillates across 50V (say a GND+150VDC on one side and GND+100-150VAC on the other, or just 50VAC), you can run that capacitor for 10,000 hours. If we drop that voltage to 25V, it'll run 20,000 hours. Raise it to 100V, it'll run 5,000 hours.

Essentially, its use

• #### Re: (Score:2)

"In this house we obey the laws of thermodynamics!"

-Homer Simpson

• #### How many? (Score:5, Funny)

on Wednesday May 21, 2014 @08:36AM (#47055577)

How many stories have we read in the last two decades about breakthroughs in power that will replace current battery technology, cut the power cord, end our dependence on carbon or make our undies clean and white on half the water? How many have resulted in actual products and a better life?

Only the clean and white one.

• #### Eh? (Score:5, Insightful)

on Wednesday May 21, 2014 @09:57AM (#47056259)

Batteries have gone through multiple generations of technology in the last two decades. Solar panels are now so cheap that the physical installation costs are the biggest part of installed costs. Solid-state storage is increasingly the norm. OLEDs are now in TVs, 77" diag. 4k-ish, WRGB. e-Paper readers cost tens of dollars and are seen as outdated tech. Smartphones cost tens of dollars. 4G phones. Gb/s Wi-Fi. Etc etc.

How much fucking progress do you need?

(When Li-Ion was introduced in '91, it stored less than 90 Wh/kg, now it's over 200 Wh/kg. The price was over \$3/Wh, and is now less than 30c/Wh. http://www.batteryuniversity.com/images/parttwo-55h.gif [batteryuniversity.com]. And there's no reason to suspect it will stop, we're still pushing Li-polymer capacity. With LiS, LiMetal, and ZnAir all in the early commercialisation stage, and graphite-everything in the lab stage.)

((Solar panels have doubled in capacity/m^2 every ten years, and halved in price/m^2. Every doubling of global production cuts the price by 1/5th. http://www.economist.com/blogs/graphicdetail/2012/12/daily-chart-19 [economist.com]. And there's no reason to suggest the trend will stop.))

• #### Re: (Score:2)

I remember watching the Computer Chronicles from the late 80's, early 90's about the new Laptops being released that feature a rechargeable battery with whopping 1.5 hours battery life! Cut to today, I only need to recharge my iPad twice a week, My 7 year old Macbook gets 3-4 hours (though, I did replace the battery not too long ago), My phone can last a week or two without a recharge. Sure, some of that was due to miniaturization and more efficient components but battery technology has vastly improved in

• #### hold a charge when it takes a lickin' (Score:3, Funny)

on Wednesday May 21, 2014 @08:40AM (#47055621)

What does this folksy nonsense actually mean? Something to do with saliva?

Yep, reckon so..gahoop gahoop gahoop.

• #### Re: (Score:2)

Have you ever tested a 9-colt with your tongue? I wouldn't try that with a similarly sized super capacitor. You are liable to bite your tongue off.

• #### bestiality is illegal and guns are not for oral us (Score:4, Funny)

on Wednesday May 21, 2014 @10:59AM (#47056933)

> a 9-colt with your tongue?

If that's a 9mm Colt, that sure sounds like a bad idea.
If you're talking about tonguing a horse - nasty.

• #### Re: (Score:2)

Have you ever tested a 9-colt with your tongue? I wouldn't try that with a similarly sized super capacitor. You are liable to bite your tongue off.

...or the antimatter "rossdee" mentioned previously:

1 milligram of antimatter could power a cellphone for a couple of thousand years or so.

• #### Nothing to do with "Liberating form Power cords" (Score:3)

on Wednesday May 21, 2014 @10:33AM (#47056609)
This "new" supercapacitor has nothing to do with liberating devices from Power Cords. Supercapacitors still need to be externally charged. All this development does is make them a bit more resilient than current model when in more rugged environment, and supposedly make it where we used supercapacitors as structural components. In other words your car would not have a separate battery to replace, because it's frame itself would be used to store electricity. While the creator seems to think that is the wave of the future, I dont see it as a particular good (or cost effective) idea.
• #### Or we could just use USB3 instead (Score:1)

A far simpler idea is just to use USB3 instead, with bidirectional power flow.

There, simpler, only one plug, no muss no fuss.

Your PS4 and xBoxOne and HDTV will still suck up as much power on standby as they do when "on", mind you.

There's your power vampire.

• #### Re: (Score:2)

Your PS4 and xBoxOne and HDTV will still suck up as much power on standby as they do when "on", mind you.

Will they? I would have imagined that the CPU in the PS4 and Xbone could shut down individual cores and perhaps even functional units when unused.

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