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The new batteries can also be recharged hundreds of thousands of times say MIT researchers

You could be charging your long lasting batteries in a matter of seconds in the future if several researchers at MIT get their way. According to a report on ScienCentralNews, researchers at MIT have discovered a new way of making batteries that involves using millions of nanotubes. Leaping over traditional battery technologies, the new types of batteries are based on capacitors, which have been around even longer than the battery itself.

A capacitor maintains a charge by relying on two metallic electrodes. The actual storage capacity of a capacitor is directly proportional to the surface area of those electrodes, and unfortunately making a capacitor in traditional battery sizes means that the electrode surface area is simply too small. To overcome this, the researchers cover the electrodes with millions of nanotube filaments, effectively increasing the surface area.

According to research team leader Joel Schindall "[the nanotube battery] could be recharged many, many times perhaps hundreds of thousands of times, and ... it could be recharged very quickly, just in a matter of seconds rather than a matter of hours." With such promise, Schindall and his team believes that the new technology will revolutionize portable electronics as well as the automotive industry. "Larger devices such as automobiles where you could regeneratively re-use the energy of motion and therefore improve the energy efficiency and fuel economy."

The research team at MIT is hoping that this new promising technology will show up in the market in less than five years from now.


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How long would the charge last?
By therealnickdanger on 8/9/2006 10:01:00 AM , Rating: 2
Seems to be the one thing missing from this exciting bit o' news...




RE: How long would the charge last?
By leviathan19 on 8/9/2006 10:02:38 AM , Rating: 2
exactly nice you can chatge the baterry in seconds but how much watts they produce and how long they last, imagine charging your laptop in 10 sec


RE: How long would the charge last?
By cgrecu77 on 8/9/2006 2:26:18 PM , Rating: 3
it doesn't matter, the key here is size, you could stack as many as of these as you need. If this is true and there's no hidden catch then it could be the biggest breakthrough since semiconductors ... the number of applications is huge and probably one of the most appealing is electric rechargable cars ...


RE: How long would the charge last?
By L1NUXownz1fUR1337 on 8/9/06, Rating: 0
RE: How long would the charge last?
By oTAL on 8/11/2006 1:12:53 AM , Rating: 2
ACtually that trend is reversing these last years... the oil companies are made of intelligent ppl who understand that money and power comes from controlling the energy sources. Since oil will soon belong to the past they are largely investing in other forms of energy.


By Shining Arcanine on 8/11/2006 12:03:08 PM , Rating: 2
Tesla Motors is designing electric cars:

http://www.teslamotors.com/

Hopefully this battery technology will be able to expand the range and durability of their vehicles tremendously. Having a car with batteries that will last 3000 to 5000 years and goes thousands of miles on a single charge is much more appealing than having a car with batteries that will last 3 to 5 years and will go 250 miles on a single charge.


Or better yet...
By Cunthor01 on 8/10/2006 12:30:25 AM , Rating: 2
...recharging your laptop via USB cable via another pc. This is the future folks.


RE: How long would the charge last?
By phaxmohdem on 8/9/2006 10:03:56 AM , Rating: 3
Good question.... This tech looks very promising if they can pull it off. Also not mentioned is how expensive these batteries are to produce compared to Li-Ion technologies.


By rrsurfer1 on 8/9/2006 10:29:05 AM , Rating: 4
It's not stated, however I was interested in this as well... so I did some research:

[from http://www.batteriesdigest.com/lihtium_ion_tutoria...]
Cathode materials have evolved from lithium cobalt oxide with energy density around 140 mAh/g (that's milliamp hours per gram of material)

[from http://www.nanosprint.com/nanotubes/newsletter/mon...]
Carbon nanotubes by themselves are able to adsorb a considerable amount of lithium. Nevertheless, the electrochemical performance of carbon nanotubes strongly depends on their structure and morphology, as well as on the level of disorder between nanotube bundles. The reversible capacity of etched multi-walled carbon nanotubes reached 681 mAh/g, exceeding the value obtained for purified multi-walled carbon nanotubes - 351 mAh/g. In the case of opened multi-walled carbon nanotubes, lithium storage capacity may get to 1281 mAh/g. Multi-walled carbon nanotubes with outer diameters of 20–50 nm exhibited a lithium storage capacity of 340 mAh/g. The capacities of single-walled carbon nanotubes vary between 450 mAh/g and 600 mAh/g.

So Standard Lithium: ~140 mAh/g
and Nanotubes: 340 - 1200 mAh/g

Now this tech may differ from what they are using at MIT, but it at least looks feasible that these batteries could store more energy, have longer life, and charge faster. Bring on the nanotubes!


By Spyvie on 8/9/2006 10:21:10 AM , Rating: 2
There was a press release about this a couple of months ago elsewhere on the web, pretty exciting technology.

The ability to charge a portable device in seconds is one thing, but this could really make electric cars useful if it comes to fruition. Even if the vehicles range is still only 100 miles or so you could “fill up” in as quickly as you can gas up today.


RE: How long would the charge last?
By OrSin on 8/9/2006 10:22:56 AM , Rating: 2
The would last a very long time. If you understand how capators works the charge doesn't just leave. This would be sweet for the car industry. Then 3 biggest ploblems are recharge rate, batter life and charge size. This would solve all the problems.


RE: How long would the charge last?
By VooDooAddict on 8/9/2006 11:10:58 AM , Rating: 3
Now we just need to make sure that the oil industry doesn't buy out the technology and bury it.


RE: How long would the charge last?
By TheDoc9 on 8/9/2006 11:46:46 AM , Rating: 2
lol, exactly. For some reason, since this will kill profits in these other industries, I doubt this technology will come to market anytime soon.


RE: How long would the charge last?
By cgrecu77 on 8/9/2006 2:29:38 PM , Rating: 3
oil is not just used for cars, and since the oil is running out anyway I doubt the oil companies would even have an interest in blocking this, au contraire, they should support it because oil prices can only raised so much until the global economy collapses which would hurt the oil companies just as much ...


RE: How long would the charge last?
By therealnickdanger on 8/9/2006 3:00:52 PM , Rating: 1
LOL, the last thing "the oil companies" would do is buy it out and bury it. Given that more of these cars on the road would result in greater electricity consumption - which is primarily dependent on coal and oil - they still win.

Also, we are not running out of oil, our production is simply not meeting demand. We find more and more recoverable oil deposits every month, more than we can probably ever use, but until we pump it out and refine it, it doesn't do us much good. So long as we don't cripple the oil industry with this "windfall" tax BS, they can use their profits for more exploration.


By Garreye on 8/9/2006 9:52:26 PM , Rating: 2
quote:
e find more and more recoverable oil deposits every month, more than we can probably ever use, but until we pump it out and refine it, it doesn't do us much good

I'd like to know where you got that from, everything I've ever read says basically the opposite of that.


By Shining Arcanine on 8/11/2006 12:08:29 PM , Rating: 2
It would actually result in lower oil and coal consumption, as electronic vehicles do not use oil and the electricity can be procured from anywhere, including coal and oil plants that have much greater efficiency than any type of car engine on the market.


By Aquila76 on 8/9/2006 2:22:09 PM , Rating: 2
I was thinking this would be sweet for long-haul semi's, too. All the equipment on board (from the accessories to refrigeration units) could be run by an array of these batteries and make the vehicle overall more efficient.


RE: How long would the charge last?
By smitty3268 on 8/9/2006 10:24:56 AM , Rating: 2
The article says that the charge of capacitors will last longer than that of a traditional chemical battery. What it doesn't mention is how much power it could hold - although it does say old ones without nanotech hold 25 times less than chemical batteries of a similar size.

It sounds to me like this is more for cars and perhaps eventually laptops, but won't be replacing AA batteries any time soon.


RE: How long would the charge last?
By Etsp on 8/9/2006 4:24:05 PM , Rating: 2
"although it does say old ones without nanotech hold 25 times less than chemical batteries of a similar size. " Lets try to compare the traditional capacitors to ones with nano-tubes... We'll use water absorbance to represent electric capacity. The
traditional capacitors would be like printer paper while the new ones would be like a fluffy cotton towel. Actually, a comparison similar to what I just said was on DT's earlier article about this subject... in any case, my point is don't use traditional capacitors as a reference to nanotube capacitors in terms of how much energy they can store.


Charging power requirements
By cmlburnett on 8/9/2006 11:04:30 AM , Rating: 5
What isn't mentioned is the power requirements to achieve "seconds" in recharge time.

Consider a 3.6 V 10 AHr battery. It would take 10 amps @ 1 hour or 1 amp @ 10 hours to charge it. So to get it done in 1 second it would require 36,000 amps. Or 10 seconds would be 3,600 amps. Assuming constant voltage during charge then you're talking 130 kW for 1 second or 13 kW for 10 seconds.

Anyone got a 130 kW electrical service at home?

Now if you're talking a hearing aide battery then you're obviously not talking 10 AHr batteries. If you're talking hybrid cars then you are also definitely not talking about 10 AHr battery packs.

A 100 mAHr 3.6V battery would require 139 W for a 10 second charge. That's quite reasonable.

A 100 AHr battery pack would require 1.3 kW for 17 minutes to charge. That's also quite reasonable, but not "seconds".

Mind you that this has absolutely nothing to do with the battery technology and assumes 100% charging efficiency!




RE: Charging power requirements
By rrsurfer1 on 8/9/2006 11:26:15 AM , Rating: 2
Obviously charging cars would be limited to either low-rate trickle type charging, or using a commercial charging station that could supply the current.


RE: Charging power requirements
By ianwhthse on 8/9/2006 11:35:04 AM , Rating: 2
Or other technologies such as regenerative braking.


RE: Charging power requirements
By rrsurfer1 on 8/9/2006 11:40:56 AM , Rating: 2
Bingo. The key is it 'allows' high current recharging, which can be useful in many situations. You can always charge slower if needed.


RE: Charging power requirements
By TheDoc9 on 8/9/2006 11:51:11 AM , Rating: 2
that is bad, but you could also use the same argument with the gas tank of a standard car.


RE: Charging power requirements
By glenzilly on 8/9/2006 12:07:33 PM , Rating: 2
"A 100 AHr battery pack would require 1.3 kW for 17 minutes to charge. That's also quite reasonable, but not "seconds"."

The typical average home has a 200 amp, 240 volt service for a total of 48,000 watts. This is then divided up between circuits ranging from 15 amps to 50 amps. Assuming a 30 amp, 240 volt circuit (a typical circuit for a dryer) you would have a total capacity of 7.2 kW. This would cut the 17 minute time down to three minutes or so. The battery charger could also be a unit that stores electrical power between charges and could reduce these times as much as is technically feasible and cost effective.


RE: Charging power requirements
By lucyfek on 8/9/2006 12:35:04 PM , Rating: 2
europe's got the advantage here - 220v in outlets makes current requirements 2x lower so it's easier to do this over existing grid. other solution (better in my opinion) is to have a "power tank" at home, trickle charge it over long time and - when needed - charge the car battery in seconds by connecting two capacitors together. in similar way commercial "charging" stations can be built (only the statons' capacitors had to be huge, but it'll be easier to hook the business up to high voltage lines). there could be problems with safety - a small capacitor can shock pretty well, now imagine what a big one can do. and the "slave" cables had to be made ofsuperconductor (at true room temparature, not available yet) or some heavy and super-thick copper. one more problem is that - according to some research that i'd read on the internet - no country has enough electricity (and grid able to handle the load) to switch to entirely electric vehicles. sad but true, but the only solution to gas prices is (and be for some time to come) to drive less.


RE: Charging power requirements
By johnsonx on 8/9/2006 4:24:52 PM , Rating: 2
The power grid in the US is 220-240 volts also. Only half is usually fed to each 'regular' outlet, but the full voltage is available in the main electrical box (and often times 1 or more 240v outlets in the garage or laundry area).


RE: Charging power requirements
By lucyfek on 8/9/2006 9:06:48 PM , Rating: 2
120/240v - i have to check on this one (and true, i know that there is big outlet for oven, dryer...but i'd thought these were 3 phaze current outlets). i don't understand why someone set stanadard voltage to 110 (it kills just like 220, but requires more expensive wiring) and transformer station with two separate volatages and power lines seem complicated (time to read somehing on this). in europe you get 220 but with some tricks you get 360V (3 phase current - maybe not in regular apartments, but at single homes, farms etc no problem) (or whatever is it).


RE: Charging power requirements
By MontagGG on 8/10/2006 7:55:31 AM , Rating: 2
Sorry to rain on you parade, but 3 phase power in US is either 230 or 460 V. Also, you guys have 50 hz power cycle, while the US has 60 hz. Higher frequency for the win!


RE: Charging power requirements
By lucyfek on 8/10/2006 10:47:37 AM , Rating: 2
well, it happens so that i've moved to States so we get wet together. i was just trying to say that 110 seems wastefull (transmission loss, more expensive wires), but i,m in no way an expert on 3p current (and the effective voltages on both sides of the pond). as the simlest example of waste - try to use a vacum cleaner (~1k) and check the power cable - hot - i've never noticed the same thing back in 220 land (unless the power cord was the sh... possible). 60 Hz - good for old tv (less flicker but lower resolution over the same band). different standards - bad for all of us (unless all the stuff you use works over any voltage/frequency)


RE: Charging power requirements
By johnsonx on 8/10/2006 1:58:15 PM , Rating: 2
no, they don't supply two different voltages. A 230v AC circuit consists of two wires, each with a 230v peak-to-valley 60hz waveform. The two waveforms are 180 degrees out of phase, so if both wires are attached to one device, it gets 230v AC. To supply power to the regular 115V outlets in a home, only 1 of the main supply wires is connected to a given circuit; the other wires in the circuit are are grounded (yes, the 'neutral' pin and the 'ground' pin in a 3-prong house plug are both grounded; there's no real difference between the two). So relative to ground, a device gets 115v AC.

(or 240/120v, or 220/110v... voltage levels vary a bit; I think the official US standard is 230/115, but I've measured anywhere from just under 110 to just over 120... seems 117 or so is what I see most often).

Secondly, transmission loss isn't an issue related to the final supply voltage. The ONLY time voltage on the wires gets as low as 240v is on the final run from the pole to the house; I don't know the exact voltages, but the voltage on the local (neighborhood) grid wires is somewhere in the 1000 volt range. The bigger lines that carry power from the substations to the local neighboorhood grids are higher again, and so on till you get to the 100,000 volt (and higher probably!) distribution lines.


By techhappy on 8/9/2006 12:57:01 PM , Rating: 2
There is enough evidence to suggest that we can already have fully electric cars that are far more efficient than internal combustion motors. We can thank Bush and the rest of the Oil Cartels for letting our pollution problems reach epidemic levels today. I would suggest seeing the documentary "Who Killed the Electric Car?" to find out more about this long history of suppressed technology.

Hopefully a discovery of this proprotion, a more efficient battery, will actually be integrated into the marketplace and not repressed like the thousands of other amazing discoveries made in the past hundred years.

Cross your fingers....




By exdeath on 8/9/2006 1:34:10 PM , Rating: 2
Lol conspiracy theories.

The reason electric cars haven't caught on is because the suck so people don't want them. Its a market problem.

For one, I personally don't like being passed by everyone else, esp since im used to being able to hit 100 on the on ramp with ease with my 4.6L 800+ HP V8

Two, I don't feel like driving out of my way to the one of two electric car charging stations and sitting there for an hour.



By danskalweb on 8/9/2006 5:41:03 PM , Rating: 3
[sarcasm] Yes, you are sooo right [/sarcasm]

[even more sarcasm] Ugly, slow electric cars, like for example the new one to be built by Lotus:

http://marketplace.publicradio.org/i/news/b_tesla_...

http://en.wikipedia.org/wiki/Tesla_Roadster


0-60 mph (100km/h) in 4 seconds

You'd better get used to being passed on the on ramp by electric cars.

Meanwhile, you better get used to paying twice as much for "gas" as you do now. (and when I say "gas" I mean petrol, not the hot, polluted gas/air coming from your mouth or your exhaust). In europe, we already pay more than twice as much as you for petrol.


Oh, and by the way, there is a reason that electric cars have been poor until now - it is because of the corrupt relationship between USA's oil and car industries.

See: http://en.wikipedia.org/wiki/Who_Killed_the_Electr...
or http://www.ev1.org

...for details of how GM deliberately and literally crushed a very successful electric car programme.


I, for one, am looking forward to a future where cars (or whatever transport we use) are powered by renewable or non-polluting sources like wind.


By exdeath on 8/9/2006 6:29:41 PM , Rating: 1
And I can buy one of those where? And charge it where? And what about people who just want the Accord they are in love with but in an electric version, instead of a roadster?

All I'm saying is that there are plenty of market barriers to electric cars, namely recharging as conveniently as pumping gas, and variety of models so that we aren't all driving the same two electric cars that give the choice of either a F1 roadster or a bar of soap. It's a chicken and egg thing.

And 0-60 mph in < 4 seconds is nothing new to me.




By cmlburnett on 8/11/2006 9:15:36 AM , Rating: 2
quote:
In europe, we already pay more than twice as much as you for petrol.


I sat down somewhat recently (within the last month) and figured this out, but I don't have the numbers handy here. If you remove any and all taxes from the cost per gallon/liter then the US pays more than Europe. Which means that you pay more because your overload government taxes you so...


By exdeath on 8/9/2006 1:35:56 PM , Rating: 2
Also is the fact that electric cars look so stupid. You can always tell them by their cheap plastic curvy 'furturistic' styling. If auto makers just offered electric versions of their current hot selling body styles, there might be more interest.


RE: Flush that Oil chugging motor down the toilet....
By JonB on 8/9/2006 2:55:06 PM , Rating: 2
An electric car equipped with these "batteries" could actually be recharged while still on the road and moving. If the standard set of batteries could go 20 or 50 or 100 miles/kilometers between charges, then the highways could have high power induction grids every 5 or 10 miles/kilometers. If you drive over the grid, you get charged to perhaps 90% capacity and then billed for the amount of power you used. Then just merge back into traffic. High power substations could keep the voltages high for quick charging. Existing gasoline stations just add induction grids to serve multiple fuel types.


By exdeath on 8/9/2006 4:10:37 PM , Rating: 2
Hmm something about being zapped with a 100kW arc... you think slot car contacts wear out fast? lol


By exdeath on 8/9/2006 4:12:53 PM , Rating: 2
Ah induction... well... hmm... having to limit power to safe levels would imply longer charge times.


By Chernobyl68 on 8/9/2006 6:41:16 PM , Rating: 2
induction grid in a freeway? not very feasible...too likely to ground itself after a period of years. and very expensive to build "new" into a road.


By Chernobyl68 on 8/9/2006 6:51:29 PM , Rating: 2
I love how those articles of the pure electric car always talk about the ease of plugging the car in in your garage overnight and letting it recharge overnight when electricity is cheaper.
OK, now picture 200 million of those vehicles charging themselves overnight. no more cheap rates.
Not to mention that I have yet to live (or ever heard of) residential power that is billed based on time of day. 99.9999% just look at your total KW-hrs. There's proposals for that kind of billing in California and maybe other places, but it would require a huge investment by the power companies for that new meter set up on your power connection. The cost of which, of course, will be passed on to the consumer.
And of course, none of that will help us folks who live in apartments and can't install that kind of equipment in our parking area.

I don't think its a bad idea, electric cars will probably be inevitable at some point (I'm thinking after we perfect Fusion power plants...! or gas reaches $40 a gallon a la SJgames "Car Wars") But its not going to be as simple as current proponents think. There's a lot of infrastructure to consider.



a little more than that
By Chernobyl68 on 8/9/2006 11:45:13 AM , Rating: 1
the amount of charge that can be stored by a capacitor is also based on the distance between the plates, and the dielectric material. Capacitors do charge faster because they're not dependant on a chamical reaction for storing charge. capacitors of the size needed to power a car would be exceptionally dangerous though...think how much power would be released if it were shorted out in a collision...




RE: a little more than that
By miniMUNCH on 8/9/2006 12:11:26 PM , Rating: 1
Yeah...the battery shorting out would be like a transformer shorting out AND then exploding.

I've seen a transformer explode...all I can say is "Gad damn!!"


RE: a little more than that
By Spyvie on 8/9/2006 12:20:47 PM , Rating: 2
Gas tanks can explode too, gasoline is poisonous and flammable, and nuclear power plants are dangerous.

In fact traveling at any speed faster than about 10mph is inherently dangerous.

I’ve seen a jillion motor start capacitors rupture, in fact they usually fail by rupturing and spilling dielectric. They don’t usually explode with any violent force though.


RE: a little more than that
By exdeath on 8/9/2006 12:36:26 PM , Rating: 2
The cause for explosion is the rapid heating and associated pressure spike caused within a liquid dielectric capacitor when large currents are dumped instantaneously. This only applies when a liquid dielectric is used as in an electrolytic capacitor.

Are these 'batteries' electrolytic or dry?


RE: a little more than that
By Larso on 8/10/2006 1:06:25 PM , Rating: 2
When gas tanks "explode", they can only release as much energy as there is oxygen to burn - not a true explosion where all energy is released at once. Though Hollywood gas tanks obey to other laws than nature's as we know :P

When your start-capacitor rupture you only release a few joules of power, if a joule at all, due to their relatively low capacity. There is no comparison to what's debated here.

The danger of high capacity batteries is no joke. We have all read about exploding laptops and heard about the security features necessary in each and every LiIon battery. Naked, charged LiIon batteries WILL explode if shortcircuited. The capacitor battery will be no different. If you have large amounts of energy contained in a small place, there is always the risk of an explosion, if the battery is able to release the energy quickly.

"In fact traveling at any speed faster than about 10mph is inherently dangerous" BS. By that logic absolutely nothing is not inherently dangerous.


RE: a little more than that
By highlandsun on 8/10/2006 11:59:04 PM , Rating: 2
The energy in such a huge capacitor probably could cause an explosion if shorted out, but that depends on the thing that caused the short. More likely it would melt and break the circuit.

There are such things as fuses too... The 12v battery in any car today could cause a nasty explosion too, why aren't you worried about that? There's a 100amp fuse on mine...


RE: a little more than that
By MadAd on 8/9/2006 12:26:59 PM , Rating: 2
I have no doubt that it would be awash with fusable links.


RE: a little more than that
By exdeath on 8/9/2006 12:29:34 PM , Rating: 2
Well first of all you would have cells of several banks of capacitors in parallel, so it’s highly unlikely that the whole battery would release its charge at once. At most you would have numerous smaller discharges instead of one great one.

And only simple fast acting fuses are required to prevent intentional electrical shorting of the main terminals of the entire bank.

What is promising about this technology is the peak instantaneous current draw allowed.
Chemical batteries have limits on the maximum current they can provide based on the rate of reaction. i.e.: short a battery with an ammeter, not only is the max current limited by the reaction speed, but the battery will be destroyed at that current due to heat released by uninhibited reaction, so not only is the maximum current limited, it’s not even attainable in practice.

A capacitor based system, provided the rest of the system could handle it, you could dump tremendous reserves instantly. Good for acceleration response in electric cars?


RE: a little more than that
By rushfan2006 on 8/9/2006 2:32:24 PM , Rating: 2
You forgot one that is big to me too....the wimpy sound...

I don't know after having 2 300hp or better sports cars in my life back to back....that actually had a nice "rumble" sound....to go to a car that sounds like a blender on steroids...just not the same feeling you know?

Oh yeah and dude...800 hp!! DAYYYYYYUMMMMMM!


News?
By horatio777 on 8/9/2006 10:36:33 AM , Rating: 2
This news was posted at the Inquirer two months ago, right after the ScienceCentral was written. It's cool story and all, but it's a little rough to be two months behind a competing news service.

http://www.theinquirer.net/default.aspx?article=32...




RE: News?
By GaryJohnson on 8/9/2006 11:13:23 AM , Rating: 2
Not only is this article two months behind theinquirer's article, it's also one month behind dailytech's.

http://www.dailytech.com/article.aspx?newsid=3043


RE: News?
By PseudoKnight on 8/9/2006 7:04:44 PM , Rating: 2
For the record, it's at least nearly seven months old as I remember reading this at technologyreview.com and sure enough it was a February article.

http://www.technologyreview.com/read_article.aspx?...


RE: News?
By Griswold on 8/9/2006 11:48:51 AM , Rating: 2
You guys missed something. This is a blog article, not a news bit.


RE: News?
By Trisped on 8/9/2006 12:59:28 PM , Rating: 2
No, both are from the news section. I had thought DT talked about this before.


RE: News?
By horatio777 on 8/9/2006 1:10:06 PM , Rating: 1
I did indeed miss that. In my defense, this 'blog' entry was the first item listed under 'Latest Headlines' on the front page. I'd say the presentation is clearly as a news piece, regardless of the source.


what about voltage change
By JAGedlion on 8/9/2006 4:20:03 PM , Rating: 2
yeah, capacitors work well for storing charge... why then aren't they used in many devices, even those used for short term battery storage (RC cars for example). Capacitors do not maintain constant voltage except of very short changes in charge (like between 100% and 95% charged type of thing) and to even out the voltage might be very difficult and perhaps very inefficient.

Also, I do belive that the grid in the US is 240 volts and is stepped down in the building as IIRC the plug going to your dryer and some other utility things (the funny v shaped prong one) is 240 volts.




RE: what about voltage change
By HueyD on 8/9/2006 4:33:15 PM , Rating: 2
Standard US Voltage is 110VAC at the breaker panel. To get 220VAC they simlpy use two lines, IE, typical dryer is 220VAC, or two 110VAC lines to nuetral, thats why the breaker for your electric dryer will take up two slots in the breaker panel.


By lemonadesoda on 8/9/2006 5:50:44 PM , Rating: 2
Oh my goodness!!! Please don't come to my home to change the lightbulbs or do any other "technical" jobs!!!


RE: what about voltage change
By Chernobyl68 on 8/9/2006 6:58:54 PM , Rating: 2
the "Grid" in the US varies from 100,000 volts to 500,000 volts. Its usually generated at around 10,000 to 15,000 volts and transformers are used to step up the AC voltage for cross country distribution (higher voltage means less current, and therefore lower I*I*R losses) and step it down when it reaches local distribution points. The residential service running up and down your street is still probably 1000's of volts. step up and step down ability of AC is why (among other reasons) edison's DC distribution system didn't work.


By JPH1121 on 8/9/2006 4:44:15 PM , Rating: 2
It's stepped down to 120v for residences and commercial buildings but I always remember seeing "[warning 50k volts] ont he power poles next to the giant transformers.

Oh, and to whomever mentioned super conductor lines or huge, thick, heavy copper lines...silver is the best conductor, better than copper or gold (gold being second best), for both heat AND electricity...hence, silver would be a better option.




By Chernobyl68 on 8/9/2006 6:59:34 PM , Rating: 2
I thought platinum was actually better?


By Chernobyl68 on 8/9/2006 7:10:27 PM , Rating: 2
Ok, I found out that silver does indeed have a higher conductivity than platinum, however platinum wiring doesn't oxidize.



By MontagGG on 8/10/2006 8:00:25 AM , Rating: 2
One of silvers greatest strengths is that silver oxide is more conductive than silver. So the old and rusted, does not reduce performance.


Toshiba
By feelingshorter on 8/9/2006 6:11:34 PM , Rating: 2
I read long ago in a news article that Toshiba was developing a battery of a similar nature where it could be recharged a 1000 time and still hold 99.9% of its charge. Toshiba might be ahead of MIT already.




RE: Toshiba
By Ars3nic on 8/10/2006 1:57:03 AM , Rating: 2
Well, what difference does it make what battery life they can have, all you would have to do is have 2 batteries, and even if the life is only 10 minutes, the other battery is charged and ready to take over...

Perpetual motion machine anyone?


RE: Toshiba
By CZroe on 8/10/2006 12:13:52 PM , Rating: 2
Still impossible. Pesky laws of thermodynamics and all.


When?
By Suomynona on 8/9/2006 10:06:47 AM , Rating: 2
quote:
The research team at MIT is hoping that this new promising technology will show up in the market in less than five years from now.


So we won't see them on the market for at least 5-6 years.




RE: When?
By rrsurfer1 on 8/9/2006 10:34:09 AM , Rating: 2
Maybe, but a significant amount of research is being dedicated to this. Big business. The winner makes a fortune replacing current battery technology. So we might be suprised!


If it can be miniaturized enough...
By CZroe on 8/10/2006 11:30:14 AM , Rating: 2
If it can be miniaturized enough, I see this as having huge implications in portable electronics WITHOUT replaceable batteries. MP3 players and ultra-portable video devices that charge from USB would no longer have a charge-degrading LiIon battery. Also, such an instant charge would imply extremely good power converion efficiency.

More things that took AA batteries would now have docks if this lasts even 10% of the life of a AA. e.g. Remote Controls and other devices that last so long between replacements/charges, like 10 months, can now last a month and you'd never notice the difference except that you don't need to buy batteries every 10 months. I have a Logitech mouse that lasts 8-mo on two AA (and can run on only one AA). It'd be perfect for that too. Electric tooth brushes and razors no longer have to be charged for long trips if it only take a few seconds to charge when you get there. Even in the home, you can set it on the base and it charges for a few seconds before shutting off and there is no constant power drain.

If performance doesn't stack up to LiIon/NiMH, I can still see dual-power devices to take advantage of this. A cell phone that is almost dead can get a near instant charge while filling up the battery for a lasting charge.

EM induction as a charge method is much more feasible when the charge can be directly stored more efficiently. I imagine that PDAs




US POWER
By upde6310 on 8/10/2006 1:46:32 PM , Rating: 2
Ok all you learned folks, here is the lowdown on US power as it ppertains to homes in the US.
There is 240 Three phase comming off the pole to your house.
You tap off of this 220 single phase for dryers and other single phase 220 use. Three phase ha three legs of 120, if you read between any two legs you have 240 volts, Three phase has to have 4 wires, three hot and a nutral. Single phase (like your dryer) has two legs of 120. You read between the two hot legs you have 240, between 1 leg and ground you have 120.
Now this is only for a certain type of transformer on the pole.
If you want to go further you need to look into 208 power.
I hope I did not confuse any of you with this!!!!

Now as for as the nano tubes in the caps, we will wait and see how this turns out.




"You can bet that Sony built a long-term business plan about being successful in Japan and that business plan is crumbling." -- Peter Moore, 24 hours before his Microsoft resignation











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