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MIT's Nano Storage Could Replace Hybrid Batteries
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.'"
Implications for Focus Fusion?
How we know is more important than what we know.
leave charged capacitors on the parts shelf to reinforce the "Don't Touch" rule? I bet one of these would reallllly hurt :-)
Si vis pacem, para bellum! For evil to succeed good men need only do nothing!
Even discounting the problems getting very high capacity with low ESR, capacitors still have a drawbacks. The charge is proportional to the voltage which means that the voltage keeps going up with more charge. On the discharge side it means that the voltage keeps reducing as you discharge the capacitor. Thus, the power supplies that are powered by capacitors need to work with a wider range of voltages. This tends to make them less efficient and more complex.
Engineering is the art of compromise.
The reality is that it will take quite a few years to test such systems for pollution, crash resistance, flexibility, and so on if used on the quantity levels required to power plug-in hybrid 100 plus mpg vehicles.
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)
-- Tigger warning: This post may contain tiggers! --
The main issue with battery technology is not amount of charge held ( there are already electric cars that can get a similar range as petrol ones ), but the batteries that have a good enough performance are very expensive and wear out after a number of years. It also takes quite a while to recharge. If super capacitors can obtain a longer lifetime then the economics may look more attractive and they also have the advantage that the recharge time is more or less limited by the rate at which you can deliver energy, rather than the performance of the storage system.
The implications are that it still won't work.
Dog is my co-pilot.
"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.You can't take the sky from me...
paradigm change Change for a pair of dimes
See also "nickel and dime you to death".
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
A battery stores energy in chemical form (sulfuric acid eventually reacts with lead, for instance), while a capacitor uses physical effects, storing energy in an electrostatic field using an insulator between two conducting plates.
Dog is my co-pilot.
As far as I can see, they have 2 big plus points:
.25in of plastic, it could easily be .24in of ultracapacitor with .01in of plastic coating. The same goes for every cosmetic part of the car that doesn't need to be transparent or comfy, as well as any structural members that the stuff turns out to have the right properties to replace. There's a hell of a lot of weight in a car that has the potential to be made out of ultracapacitor instead of whatever it's made of now.
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 dashboard being
A pizza of radius z and thickness a has a volume of pi z z a
I'm sticking with my 2006 GTO with the 6.0 V8 engine. Yeah it gets lousy mileage but I figure that if I go places really, really fast then I'm not polluting for as long as all those other people. Plus I'm helping to get rid of all that messy oil. As soon as that stuff is all used up we'll see real progress towards an alternative.
I'm doing it FOR the planet.
Appended to the end of comments you post. 120 chars.
A capacitor has to hold the positively and negative charged portions of itself nearby, but electrically isolated; to keep the insulation from being crushed (opposite charges attract, remember) requires a certain physical strength proportinal the the charge stored that will put at least a top-end limit on capacitor capacity.
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.
you forgot two other important differences. Weight, and toxic chemicals. Super capacitors are far cleaner and easier to dispose of later. Also the Chemical that make up large battery banks are very heavy. If you can shave 500 pounds off of a car just by removing the batteries and replacing them with equal sized super capacitors then your electric car will be a lot more efficient over the long haul.
i thought once I was found, but it was only a dream.
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
"THERE IS NO JUSTICE, THERE IS ONLY ME." -Death
So, how is all the new demands for electricity going to be satisfied.
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.
Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
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
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.
And just because they aren't investing specifically at MIT doesn't mean they aren't investing in this sort of research.
1) Li-ion batteries use no toxic components in manufacture, and while conventional li-ions have some chemicals that are poisonous in the end products, A) the latest generations of them designed for automotive use lose those (such as using nicer electrolytes and replacing the LiCoO2 cathode), and B) they break down harmlessly once disposed (no heavy metals or the like).
2) For a given amount of charge, an ultracapacitor is a lot *heavier* than a battery bank. They're lower energy density (assuming EEStor doesn't pull off a miracle).
If Assange fell off a cliff, his ghost would declare it a victory.
No ripping up of massive stretches of road needed. It can be done as an incremental process. Step one, vehicles are increasingly electrified (already increasingly underway). Step two, the vehicles are designed to have inductive chargers and any new or repaved roads have chargers/meters installed. The vehicles still need to have sufficient battery or gasoline power to keep going a relevant distance when there are no suitable roads around. Step three, enough roads in some places are converted that cars can start ditching energy storage/backup engines. Those who want to be able to offroad can still get vehicles with extended range.
:) Same sort of concept. Your vehicle has an identifying chip and transponder, and the road meters you. No identifier, no juice. Or, if that proved too costly, it'd be easy enough to have the occasional random bit of "smart road" that checks to see if you're stealing power, connected to a concealed camera to photograph cheats.
Incremental changes tend to work a lot better than radical departures, especially when the capital costs are as huge as in the case of replacing our entire transportation infrastructure.
As for the person who asked about who would pay -- that's easy. Ever seen an EZ-Pass toll booth?
If Assange fell off a cliff, his ghost would declare it a victory.
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.
Not a typewriter
Providing electricity to parking areas in apartment buildings is not much more difficult or costly than providing lighting. In cold climates, parking slots with 120V plug ins are routinely provided for apartment dwellers to power block heaters (for example, check the specs on Minot University student housing apartments in North Dakota). Hell, I have heard that sometimes even movie theaters have them for public use in non-assigned parking spaces (any Alaska dwellers with first-person support?). The only reason that there is a 'last 10 feet' problem is that there is absolutely bone-zero real demand for a solution. The electrical infrastructure is really a non-issue, it's the rolling storage that's the hold-up.
All the systems of this nature I've seen only work while the vehicle is resting and contain an RF tag that handshakes with the vehicle and turns off the coil while it's not in use. In China, they're used at bus stops, so the bus can charge while people are getting on and off. They could also be embedded at traffic lights, so if you stop when the lights are red you can recharge your car a bit. If they can get the switching to happen fast enough then it might be feasible to use them while in motion, but I suspect not for a long time.
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