


MIT's Nano Storage Could Replace Hybrid Batteries 191
mattnyc99 writes "Last week we discussed Popular Mechanics' reporting from MIT, but missed one of the coolest breakthrough of all, something scientists have been working on quietly as Detroit spends money elsewhere. The Lab for Electromagnetic and Electronic Systems has been doing some mega-efficient work with ultracapacitors, which store drastically less energy than a battery but have essentially none of the drawbacks — especially via carbon nanotube arrays. Automotive experts say the new research is enough to start replacing batteries in hybrid cars, and plug-in vehicles might not be far behind. From the scientist who thinks ultracapacitors are potential competitors for the pack in his Toyota Prius: 'I try to contain myself, because it hasn't been proven yet, but it could be a real paradigm change.'"
Better capacitors (Score:4, Interesting)
Capacitors have drawbacks too (Score:5, Informative)
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Additionally I could see a solution in which not all capacitors are use at the same time. By activating them in a proper order/way, one could make a more constant source that can then be the input for a SMPS.
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Re:Capacitors have drawbacks too (Score:4, Funny)
Y'know, I was thinking about going into Tosche Station to pick up some of those...
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Do you think all they work on at MIT becomes the Next Big Thing? If I'm working on supercapacitors, and EVs are hot, mentioning applications in EVs in a press release is a good idea if I hope to get funded next year.
I'll even add another criticism of the tech; Power densities will always be so low (theoretical limits) that the bulk of the storage in a vehicle will always be battery based. LiFePo batteries, for example, solve many of the p
Focus fusion (Score:3, Insightful)
Did anybody elses Science Teacher (Score:3, Interesting)
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No. I think yours just had it in for you. You should've left the lithium where it was....
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Re:Did anybody elses Science Teacher (Score:5, Funny)
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The Manhattan Project (Score:2)
leave charged capacitors on the parts shelf to reinforce the "Don't Touch" rule? I bet one of these would reallllly hurt :-)
Especially if they're for photo strobes.
FalconRe: (Score:2)
less than batteries? (Score:2)
Re:less than batteries? (Score:4, Informative)
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Regenerative braking plays a big role there. Right now, a lot of energy from the brakes on electrics/hybrids is lost to heat because the battery can't absorb the charge fast enough. Adding a supercap (even if it's just a few) would greatly increase overall efficiency.
But in general, supercaps are dumb if they're used alone. Caps are good for storing and releasing a lot of charge very quickly, not letting it bleed out slowly.
Re:less than batteries? (Score:4, Insightful)
Re:less than batteries? (Score:5, Informative)
2) For a given amount of charge, an ultracapacitor is a lot *heavier* than a battery bank. They're lower energy density (assuming EEStor [wikipedia.org] doesn't pull off a miracle).
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3) Capacitor is also bigger. There is already some complaints about the size of the battery pack in Priuses.
How about on-the-go charging? (Score:2)
Anyhow, after seeing that,
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Great, but how do you pay for the electricity you use? I guess you could add it to the toll booths for freeways, but what
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I'm not sure that can work, after all the other cars who DO have a "EZ-Jolt" tag would like to get the electricity they're paying for even when they're driving alongside a car who isn't paying.
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who will pay? (Score:2)
As for the person who asked about who would pay -- that's easy. Ever seen an EZ-Pass toll booth? :)
A bunch of people refuse to use those EZ-passes though. What about them? And who will run such a system, the government or a government granted monopoly? Then what could the data collected by whoever it is be used for?
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Seems to me this talk about using inductive chargers is shooting way above the target.
We've got the means right now to charge electric cars on the go. We know how to string catenaries and how to build pantographs that can can be raised to grab the juice, even at high speeds, or lowered when going off grid. All we need to do is transfer the technology we've developed for electrified light rail to toll lanes on the freeways and main streets.
Got charge enough on board and don't want to fuss with the cats a
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You've got to be kidding. You want to have huge coils of wire embedded in the roadway, sitting there day and night drawing incredible amounts of current? Oh, and by the way, are you forgetting how a magnetic field diminishes with distance? Iron-core transformers are pretty close to 100% efficient, but you add an air gap, even a small one, and the efficiency dimishes dramatically. In short what you're suggesting is utterly preposterous.
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'"In order to prolong the life of the battery in my car, they only use it over the middle 10 to 15 percent of its range he says. "So actually I'm only using perhaps 15 percent of the capacity. With an ultracapacitor you can use it all, or almost all."'
So, if you're only using 10%-15% of the battery, then 5% for current ultracapacitor isn't too far off. With the ultracapacitor you don't have to worry about battery memory or the explosiveness of LiIon. So, in the researcher's eyes, thi
rtfa (Score:5, Informative)
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There is still a danger - Capacitors that store a lot of energy use very very thin insulators to separate large sheets of foil charged to large voltages. Insulators are only good for a certain number of volts per meter, and they won't make them much thicker than they need to be - it would reduce the capacity. Imperfection
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2) Modern automotive li-ions are rated for a decade or two of service.
3) Modern automotive li-ions are non-explosive. Compare, for example, this A123 battery with a traditional li-ion [youtube.com].
4) Many modern automotive li-ions have very fast recharge times -- 5-15 minutes, depending on the type.
Don't get me wrong -- ultracapacitors are great. But until they can increase their energy density by an order of magnitude, they're only competing against the batteries in hybrids (and not p
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That they can be cycled as many times as you like without degrading, and they don't get damaged by being totally discharged. This opens up possibilities like contunially topping them back up with recovered braking energy, as well as getting rid of the buffer needed to prevent total discharge with conventional batteries.
Secondly, they are not volatile, so they could be built into a lot of places where you couldn't put a lead/acid battery - instead of your dash
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you ARE joking, right? That large sheet of plastic, right in front of your face, and you want to use it to store an electrical charge? A charge sufficiently large enough to move a ton down the road. I'm assuming in your perfect world, no one ever gets in a crash.
Please.
The same goes for every cosmetic part of the car that doesn't need to be transparent or comfy
Every part of the
Boom! (Score:2)
Amazingly enough, there's this thing called a ground. Ever wonder why a lightning strike on a vehicle doesn't vaporize the occupants? In almost every way, an ultracapacitor is safer than a tank full of gasoline.
Vehicle occupants aren't vaporized because electricity tends to flow along the outside of conductive objects, and the occupants are inside. It may cause some heating, but the car's body has low resistance and most of the power is dissipated in the ground.
If the dielectric was pierced, one plate of the ultracapacitor would "ground" to the other plate, not the earth, releasing all the stored energy in an instant.
An ultracapacitor sufficient to power a car would have around as much energy as a lightning
Please apply for a position at MIT (Score:2)
But give the freaking MIT scientists a break, eh?
Re:less than batteries? (Score:5, Informative)
Probably already addressed adequately by other responders, but I'll chime in.
At the moment, ultra-capacitors may be best suited for systems such as hybrids where you have a constant, low power source such as a small generator in a hybrid. The idea being that you could get good power/acceleration out of a capacitor when needed and the rest of the time is spent recharging from the motor. All without the disadvantages of batteries. Think of it as a sort of electrical flywheel.
-matthew
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Hmmm. (Score:2)
Now, how does that compare to the MIT model? Well, MIT is in the open and is being tested by a number of folks. IOW, their current values are
Think of this as the Future not as the Present (Score:3, Insightful)
During this time, it would be logical to buy one of the 2009 or 2010 model year plug-in hybrids that will be on the market - and then ten years down the road see if a battery pack replacement using this capacitor technology is on the market and cheap enough due to large scale production to implement.
Do now. Not ten years in the future.
(p.s. a cure for half of all cancers is being tested in the UK right now, but it takes almost a decade to do the trials before it comes to market)
Plug-In (Score:2)
My (tentative) plan is to use a hybrid Battery/UltraCapacitor design for "burstable" speed where batteries are lacking.
Perhaps if this new design works its way out into the wild, I will opt for a pure ultra-capacitor design? I doubt it, but it certainly would be cool. Recharge times would be very, very fast.
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My (tentative) plan is to use a hybrid Battery/UltraCapacitor design for "burstable" speed where batteries are lacking.
I suggested this on the EAA-PHEV mailing list, as a way to buffer the battery storage system from heavy draws (i.e. hard acceleration) although I don't think anything ever came of it. The trick is going to be to isolate the capacitor(s) from the battery storage system during the heavy draw, so the motor pulls the power from the capacitor. I suggest doing this by determining the accelerator position/rate of travel (off to floor in under X milliseconds = ultra capacitor bursting).
If you do decide to go wit
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It only looks like it's from the 1930s...
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Excepting EEStor pulling off a real
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You DO realize your drive times will always be shorter than your recharge times, right?
Ka Booooooom!!! (Score:5, Informative)
"And by avoiding the chemical reaction that drives traditional batteries, there's no real danger of a capacitor suddenly overloading--or exploding like a laptop's lithium-ion battery pack."
They won't explode like a lithium-ion battery pack, it will be a 100X worse.
If anything pierces the dielectric, all the energy stored in the capacitor will discharge violently in milliseconds.Re:Ka Booooooom!!! (Score:5, Funny)
I hear something like this happens with condoms too.
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Lots of stored energy is bad. And the solution is...?
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Gas tanks don't explode. It takes 3 things to get something to burn. Oxygen, Heat, Fuel. To get something to explode, the fuel needs to be dispersed in the oxgen and there needs to be enough oxygen to support the explosion.
There is hardly any oxygen in a gas tank.
There's an episode of Mythbuster where they shoot tracer rounds (burning bullets) into a gas tank and can't get it to explode. Not enough oxygen, and the fuel isn't dispersed in the oxygen.
Batteries are OK in that the rate of discharge is limit
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Lets take your 400 miles of charge (100 kw/h) and break it into 1000+ watch battery sized devices.
Sure if one gets pierced it is bad, but a well grounded system will prevent the others from melting while the one goes Ka BOOOOOOM.
Not only that, but I bet it will be cheaper to manufacture them in mass when they are small.
Re:Ka Booooooom!!! (Score:4, Informative)
Also, boats -- particularly inboards, are more dangerous. Gas vapor is heavier than air so it tends to collect in the bilge area, whereas a car has open air beneath it. That's why you're supposed to run the blower for a bit before attempting to start a boat engine.
Everyone may think putting capacitors in a car is a good thing, but you're essentially mounting bombs in the car.
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There's still internal resistance, ya know. I imagine it being more along the lines of a meltdown. A molten capacitor burning/melting a hole right down through the car onto the road.
Would be interesting to test, anyway. Maybe a job for the Mythbusters?
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Theoretical limit of capacitors? (Score:2)
What is the theoretical limit of a capacitor? That is, if you could somehow place all the atoms exactly where you wanted, what's the energy/weight ratio you could obtain?
Re:Theoretical limit of capacitors? (Score:5, Interesting)
Interestingly, this is dependent (duh) on the strength (energy) of chemical bonds, so IIRC, the theoretical limit for capacitors is actually pretty much the same as for chemical fuels or batteries. (Now, small electric motors are more efficient than small engines, so electric systems can be a huge win, although the fuel system don't have to carry their own oxidizer...blah blah blah.)
Pretty much anything non-nuclear (you can throw flywheels, nanotech windup springs, and what have you in, too), should in a perfect world max out at roughly the same magnitude because they're all fundamenentally dependent on that chemical bond strength.
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I think electrical discharge in the dialectric would happen before physical breakdown in some cases.
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Perhaps the most interesting concept for high storage ultrapacitors out there right now is EEStor's barium titanate supercapacitors. Individual grains of barium titanate have an incredibly high permittivity of 18,500, but there are two problems. One is the af
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I saw a references to 3500W fuse. Assuming that is the upper limit, it would take three hours to provide the same amount of energy as one kg of diesel (which is apparently larger than one Liter). Filling the capacitors could be slow or dangerous.
How much of diesel's energy is actually realized though? I've heard that IC engines lose half of their energy to heat. That lowers the ratio to 15:1 (although I'm not considering the efficiency of ultra
Difference between battery and capacitor (Score:2)
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Obligatory EEstor reference (Score:2)
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And yet (Score:2)
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I read the article you linked, and it doesn't seem to claim that. In the article, Lockheed said "We haven't personally tested their [eestor's] prototypes yet."
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It does claim that, here is the relevant section quoted:
"Q: Do their caps hold 10x the energy at 1/10th the weight of a lead acid battery?"
"A: Yes."
You misread it (Score:2)
I dunno guys (Score:4, Funny)
I'm doing it FOR the planet.
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Interesting but totally unrelated sidenote, the first mad max film (road warrior in the US) opened with max chasing down (and killing) an outlaw in a 70's era Holden Monaro.
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Reminds me of the joke about the blond who got pulled over for speeding. Cops asks her why she was speeding. She says "Because I was running low on gas and need to make it to the next gas station before I run out."
OK, not really much of a joke..... but still. Your post reminded me of it.
-matthew
Electricity (Score:4, Interesting)
I know everyone likes Electricity and such, but current demands are taxing the existing power grid / infrastructure.
And with all the NIMBYs out there, nobody is willing to build new and needed Hydro Electric, Nuclear, Coal powered plants anytime soon. So, the result is "cool, electric cars, but I can't use them because of the blackouts". And I don't assume that somehow people will give up the NIMBY attitudes for an electric car.
Its easy to be an environmentalist, you don't have to think of the requirements to achieve whatever goals you might have. It just has to sound good.
Re:Electricity (Score:4, Insightful)
Power demands are much lower at night, so a population charging electric cars at night might allow us to make more efficient use of the grid all day long, instead of building it to handle a peak load it only sees 2 hours a day.
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That's one of the things never really touched on in these elec car discussions. Where, exactly, do you recharge it. Not everyone has a garage. Electric cars would be very well suited to a city environment. But...where and how do you recharge it if you live in an apartment? Can't run an extension cod out the 5th floor window. And a parking meter type charging station is at the mercy of any little asshat unplugging your car
Sigh (Score:2)
First, if the electric cars use UC, then no doubt filling stations will pop up ALL over. In fact, I suspect that regular gas stations will add these quickly (as in under a decade).
Second, as to the home recharging, there is little doubt that both gov AND utilities will work together to push this. WHy? Because it allows utilities to run larger base load plants (i.e. nukes). AE is difficult on Utilities unless they use something like Natural Gas. But if
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Not problems, practicalities. This is just like the last mile question with ISP's. But instead, it's the 'last 10 feet'. How we get the actual power to the battery/UC/whatever? If the recharge times are quick enough, then centralized stations (as we have now) are good enough. But if it takes more than, say, 30 minutes, then it will have to be done at home. And thence the apartment question comes into play.
I don't have a solution. But it is a questio
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I know everyone likes Electricity and such, but current demands are taxing the existing power grid / infrastructure.
They include a new long haul HVDC grid in the proposal.
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We already know dozens of ways to generate electrical power, and any one of them would work fine. It's a solved problem. The NIMBY and load problems you mention are merely political and engineering challenges, and they will be resolved when it becomes economically necessary to resolve them.
Its easy to be an environmentalist, you don't have to think of the requirements to achieve whatever goals you might have. It just has to sound good.
No
Re:Electricity (Score:4, Informative)
And it's easy to insult environmentalists when you don't know what you're talking about. We already have tons of spare generating capacity for EVs and PHEVs -- everywhere except the pacific northwest. And even if we had to build more, as if electricity infrastructure was somehow more expensive to build and operate than oil infrastructure (it's far cheaper -- that's part of why a joule of electricity costs so much less than a joule of gasoline). [pnl.gov]
Why electric cars? Here's a primer [daughtersoftiresias.org].
They've come a long way (Score:3, Interesting)
An alternative was to purchase existing 1 farad supercaps and build the required capacitance through series and parallel circuits to get the voltage and capacitance up. The cost was over $250,000 at the time. The last issue was building a charging circuit that could quickly charge the cap up within 30 minutes.
I also explored the design of making a 200 mph electric dragster. The issue was the megawatts of electrical energy that needs to be transferred within 6 seconds to the electric motors. It was the equivalent of a large electrical explosion. Here's the latest world record electric dragster at 160 mph: Dennis "Kilowatt" Berube [teva2.com]
Detroit spending money elsewhere? (Score:3, Insightful)
I find it amusing that the summary takes a jab at American automakers in light of the fact that Ford has an on-going partnership with MIT. Whether Ford's funding is supporting this specific project I can't confirm, but clearly they are funding these types of projects. A press release describing the partnership can be found here [mit.edu].
And just because they aren't investing specifically at MIT doesn't mean they aren't investing in this sort of research.
Popular Mechanics blows it again (Score:2)
Let's look at the actual paper from MIT [mit.edu]:
Ultracapacitors or double layer capacitors (DLCs) are energy storage devices whose operation is based on the double layer effect [1]. By utilizing highly porous carbon material with a surface area up to 2000m2/g as electrodes (as in Fig. 3) commercial DLCs can achieve a energy density (6Wh/kg) much greater than the energy density of a conventional capacitor. However, this figure is much lower than the energy density reached by Lithium-Ion batteries (120Wh/kg).
Pr
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Re:Paradigm? (Score:5, Funny)
See also "nickel and dime you to death".
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Defining nanotechnology. (Score:2)
The technology must involve constructing mechanical structures where the position of each atom in the structure and its bonds to its neighbors are all controlled - in a mechanical engineering rather than a chemical reaction sense. (Biochemistry is a "found nanotech" - and was the proof of concept.) Think of it as industrial Tinkertoys (tm) where the spools are atoms and the rods are chemical bonds.
It's called "nanotechnology" be