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MIT's Nano Storage Could Replace Hybrid Batteries
Posted by
Zonk
on Mon Mar 03, 2008 05:12 PM
from the replace-the-darn-bunny dept.
from the replace-the-darn-bunny dept.
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.'"
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Technology: New Wave of Fusion and Robot Innovation at MIT 90 comments
An anonymous reader writes "Popular Mechanics has been getting some great access inside the labs at MIT all week, and they've gotten some interesting looks at developing technologies. Robot-assisted rehab with gaming-style controllers comes out of the biomechanics lab, blind and crash-proof UAV testing with F/X cameras is being done at the aerospace controls lab, and work on electric scooters with super-cheap assembly is proceeding at the Media Lab. Perhaps most exciting is a fight for funding while the holy grail of clean fusion power in reach at the plasma center. The article on fusion predicts, "We'd see economically feasible fusion power by 2035, at the earliest, and increasingly efficient commercial reactors somewhere in the middle of the century."
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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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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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less than batteries? (Score:2)
Re:less than batteries? (Score:4, Informative)
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Re:less than batteries? (Score:4, Insightful)
Parent
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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How about on-the-go charging? (Score:2)
Anyhow, after seeing that,
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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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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
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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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
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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Re: (Score:3, Interesting)
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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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.
Parent
Difference between battery and capacitor (Score:2)
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Obligatory EEstor reference (Score:2)
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And yet (Score:2)
I dunno guys (Score:4, Funny)
I'm doing it FOR the planet.
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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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].
Parent
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.
Re:Paradigm? (Score:5, Funny)
See also "nickel and dime you to death".
Parent