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NASA Power Science Technology

Researchers Develop Super Batteries From Aerogel 182

greenerd writes "Researchers from the University of Central Florida may have found the most efficient (and most bizarre) battery material yet – 'frozen smoke', also known as Aerogel. One of the world's lightest solids, aerogel contains multi-walled carbon nanotubes (MWCNT) which each one several thousands thinner than human hair. The researchers, Associate Professor Lei Zhai and Postdoctoral Associate Jianhua Zou, believe that this material could soon become the best energy storage material for capacitors and batteries."
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Researchers Develop Super Batteries From Aerogel

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  • by rolfwind ( 528248 ) on Saturday March 05, 2011 @10:19PM (#35393716)

    For insulation as well. Several companies make it, but hard to get a hold of a decent size of it at anywhere near an economical price.

    Hopefully this spurns added demand to find a cheap way to produce it en masse.

    • by Anonymous Coward on Saturday March 05, 2011 @10:24PM (#35393738)

      demand is already ASTRONOMICAL

      • Aerogel is usually formed from silica gel, or sometimes from a sort of carbon fiber paper. The material that the article talks about, which is an airy mass of carbon nanotubes produced by vapor deposition is not an aerogel. See: http://en.wikipedia.org/wiki/Aerogel#Carbon [wikipedia.org]
        • I can't speak to the material in the article, but aerogels are made from all kinds of materials, not just silica. Silica aerogel was possibly the first aerogel. Carbon aerogels are real aerogels, and made by baking organic aerogels. They can be further altered under steam and pressure. That is the normal process for making superconducting capacitors (ultracapacitors).

    • I saw this [msn.com] two or so years ago. When I searched a few minutes ago, I can't find that it's gone anywhere, but it's not yet been very long.

    • by LongearedBat ( 1665481 ) on Saturday March 05, 2011 @11:22PM (#35394042)
      A house using its insulation as a battery would mean a pretty big battery. With lots of these houses, we could save alot of the energy generated during the night (currently lost, thus wasted due to low demand) to be returned to the grid for use during the day, and especially the evening (peak usage period).
      • With lots of these houses, we could save alot of the energy generated during the night (currently lost, thus wasted due to low demand)

        There is nothing to be saved at night. Thats a miss conception.
        In the electric grid no energy is produced that is not used somewhere. The grid would collapse if you would pump in energy that is not taken out somewhere else.

        angel'o'sphere

        • by wagnerrp ( 1305589 ) on Sunday March 06, 2011 @12:03AM (#35394194)

          Technically, you are correct. However, power companies have to run peak load plants to make up the difference in power draw from what the baseline plants provide. If you can come up with an economical means of storing vast amounts of energy, you would be able to build and operate more baseline plants, and do away with the more expensive, less efficient, peak plants.

          Similarly, if you can provide a significant energy buffer, otherwise unreliable power sources like wind and solar become considerably more viable.

          • by Rei ( 128717 ) on Sunday March 06, 2011 @02:03AM (#35394684) Homepage

            There's also "spinning standby", where you keep the boilers hot and the generator turning over but not producing power so that you can produce power on short notice. The grid has to be able to respond quickly, since there's not exactly a ton of capacitance in the wires to buffer demand fluctuations.

            That's one of the things that I find so amusing about the people who rail against wind and solar power: "You'll ruin the grid by making production unstable!" Um, hello, *demand* is already unstable, which is effectively the same thing; this is nothing new. You do increase the need for peaking capacity, but this is overall an issue already very familiar to grid operators.

            • Our local electric utility [pseg.com] has been installing solar panels on telephone poles all over the place. They have computer controlled inverters that supply the grid based on demand.
            • by sjames ( 1099 )

              The difficulty of wind power is that it is closely correlated. A bunch of households will randomly switch things on and off without any correlation, but the wind rarely dies down or picks up for just one windmill in a field or even just one field in an area. That said, it doesn't mean wind power is useless, it just means we need to develop better technology to smooth the output.

              • No. We need a "smart grid". Let power prices fluctuate with supply. Tell the appliances (over the internet) what the current price is. Let heavy power use appliances like the battery in electric cars, the fridge, the airco and the electric boiler switch on at a pre set price (settable by the user) or make a simple schedule: "Charge my car preferably when the price is below 0.05 ct/ KWH, but make damn sure the car is charged when I want to go to work in the morning". This would let the demand follow the supp
      • With lots of these houses, we could save alot of the energy generated during the night.

        In future, you might want to consider fixing your typos, rather than just making them bold.

        • With lots of these houses, we could save alot of the energy generated during the night.

          In future, you might want to consider fixing your typos, rather than just making them bold.

          Hmmm... screw the typo, the logic failure is astounding... "With lots of these houses, we could save alot [sic] of the energy generated during the night".

          I'm confused, does he mean lots of us could charge our houses' batteries during off-peak times and use that stored power when energy prices are higher in order to save money (which, with a large enough number of homes using this strategy will eliminate the usage-peak altogether or even shift the electric consumption peak to the night such that the monet

    • by Zerth ( 26112 ) on Sunday March 06, 2011 @01:11AM (#35394482)

      You can make an aerogel suitable for home insulation purposes yourself. Just requires some practice, a 10 year old kid did it back in 2002.

      http://www.wired.com/geekdad/2008/03/ten-year-old-ma/ [wired.com]

      Also, there are several companies producing aerogel insulation sheets for the few places regular insulation doesn't make sense. e.g. really thin walls or shims between framing. Anywhere you aren't space constrained, you're probably better off just adding more conventional insulation.

      • by Rei ( 128717 )

        Aerogel is starting to make its way into backpacking gear -- for example, ground rolls. Of course, some designers stupidly just assume "High R value = Keeps you warm" and ignore the infrared aspect.

    • inhabibat.com wrote, The researchers, Associate Professor Lei Zhai and Postdoctoral Associate Jianhua Zou, believe that this material could soon become the best energy storage material for capacitors and batteries.

      More fluff technology journalism. Energy storage materials for capacitors are quite different from energy storage materials for batteries (no chemical reaction takes place when capacitors are charged or discharged). These "multi-walled carbon nanotubes" can't be used for both applications; I sus

      • Built one way they make great ultra-capacitors. In fact aerogels are the material of choice for ultra-capacitors.

        It is not difficult to dope these aerogels with metal salts. If one of these doping agents resulted in a carbon-lithium aerogel, you could fill it with an electrolyte and make highly efficient lithium batteries packed in a small space. This would be an outstanding battery for long distance batteries in automotive vehicles. Or even for aircraft.

        Carbon aerogels have been doped in the past with meta

  • Actual Headline: (Score:5, Insightful)

    by Anonymous Coward on Saturday March 05, 2011 @10:20PM (#35393724)

    Researchers Didn't Develop Super Batteries From Aerogel

    • by tsa ( 15680 )

      Indeed. And the article is rubbish, too. No details whatsoever, just someone who says that maybe you can make batteries out of it.

      • by jamesh ( 87723 )

        When the signoff line in TFA is a stupid comment over what to call it, you know they definitely aren't onto something.

      • by Rei ( 128717 )

        My reaction exactly. It's awful. And they didn't even mention that they're not talking about what is generally meant by "aerogel" -- silicon dioxide aerogel. They're talking about a less common form, carbon aerogel.

        An interconnected mesh of carbon nanotubes is not a storage mechanism. It's not a capacitor. It's not a battery. It could perhaps be used as a scaffolding to store active anode or cathode materials -- but they haven't done that. And I have no clue how they'd go about making that into a cap

        • (In typical slashdot fashion--) I have not read the article.

          However, I am familiar enough with existing ultra-capacitors to know that the proposal given by the summary is not exactly new. This is the fairly obvious evolution of existing activated carbon based ultra-capacitors. Obligagory wikipedia [wikipedia.org]

          The difference between the two would be that the electrolyte soaked aerogel would have far greater effective surface area than would the activated carbon, which effectively WOULD increase it's charge storage capaci

          • Actually, most modern facilities use CO2 as the solvent, ok all, and these aerogels can be quite large. They use some in the LHC. There are some rather large manufacturing facilities making this stuff. Think in the tens of thousands of gallons and you're getting closer to the mark.

  • If this means more research into cheaply producing areogels, that would be great. This stuff is the best insulation material (for heat) imaginable. Put that in my walls and attic, and my heating bills would go way down. Too bad it's completely impractical right now. Develop a spray-on areogel that's inexpensive and fire resistant, and you would transform the building industry.

    • I heard once that a house lined with aerogel could be heated with one candle. Very interesting stuff. Read the Wiki page on it, there's a list of applications including cleaning up spills, thickening agents, and trapping space dust from comets.
      • by Pharmboy ( 216950 ) on Saturday March 05, 2011 @11:05PM (#35393964) Journal

        Likely, very much an overstatement. Wood and glass are terrible insulators, and since houses need windows and wood studs (generally), you will still need more BTUs than a candle to heat it. Windows and doors are your major heat losers right now. At least where I live (NC), you are required to put insulation in the walls and attic of any home you build, or remodel over 50%, so it isn't like the homes don't already have reasonable insulation.

        Still, it would be a much *better* insulation that could cut heat bills by a large degree, but not 99%.

        • Re: (Score:2, Informative)

          Wood and glass are terrible insulators [...]

          That is bullshit. Both are excellent insulators.
          Take one in the hand and put the other end into fire. (Either wood or glass, does not matter), your hand stays cold.
          A problem are windows because they are difficult to get tight and they lose heat by radiation, but that has nothing to do with insulation. You can fix that problem by using multiple sheets of glass separated by air and different kinds of glass.

          angel'o'sphere

          • by the eric conspiracy ( 20178 ) on Sunday March 06, 2011 @12:32AM (#35394302)

            Total rubbish. Glass only has an R value of 0.14 and softwoods about 1.4. Polyurethane foam is around 7-8.

            • by buback ( 144189 )

              The key here is heat is a very tricky thing, and there are multiple ways it is transmitted. Wood is a good insulator, but compared to what? metal?

              what if you compare wood to air? air is a much better insulator, but it tends to move around and to bump into other air, which moves the heat around.

              Glass is a good insulator too. many of you probably melted glass tubing in one of your science classes in High school (probably chemistry). you were holding in your uninsulated hand a glass tube that melts at ~1500 de

          • Complete and total nonsense. Glass is a terrible insulator on its own. The vacuum between the glass panes however is a great insulator. In newer windows, there are even three panes with inert gasses between the panes which is even more effective than vacuum.

          • by pz ( 113803 )

            You can fix that problem by using multiple sheets of glass separated by air and different kinds of glass.

            The reason multi-glazed windows are more thermally efficient is because you are restricting convective airflow. Glass is a reasonably good thermal conductor (although not an excellent one) compared to many other materials. The reason that even well-sealed windows are a heat conductor is because there is free airflow on both sides of the glass. Adding additional panes reduces the conductivity by restricting airflow.

          • As someone else pointed out, glass is a terrible insulator and it is the inert gases between the layers of glass that do the insulating. The only reason that glass is used is because it can hold the inert gases in place and is transparent, it adds virtually nothing to the insulating value.

            And if wood was a good insulator (it isn't) then everyone would have log cabins. Even newer log cabin kits come with logs that are hollowed out and filled with insulation, as solid wood is terrible for keeping out the co

        • by afidel ( 530433 )
          It's R45 per inch vs 7.2 for the best commercially available foil faced insulation so it could reduce bills by a significant percentage. One interesting use is thermalblok, a 10mmx1.75" strip that you can apply to the studs to increase the structures R value by up to 40%. Only costs $1/ft.
        • Makes me wonder how you would go using vacuum to insulate a building.

          • By sealing an aerogel package in mylar, which makes a very strong material with an even higher R value than "naked" aerogel, with a radiant barrier included for even more energy conservation. And incidentally an even lighter material, as the vacuum replaces heavier air.

      • by Rei ( 128717 )

        Aerogel does not block IR. It has an excellent R-value, but R-value is not about radiation.

        • Incorrect; Both commonly created aerogel species (Silicon dioxide aerogel, and carbon based aerogel) are extremely opaque at infrared wavelengths.

            • If you note, their sample involves *anhydrous* silicagel based aerogel, which would not be indicative of silica aerogel that is being employed as home insulation.

              The silica gel would absorb water due to it's high hygroscopic tendencies, and then lose a lot of the IR transparency they are discussing.
              As seen here [sciencedirect.com]

              Also, Carbon aerogels are another beast entirely, and are EXTREMELY IR opaque.

              • by Rei ( 128717 )

                So your argument is that, at best, it'd gain the IR absorption capability of a tiny amount of water vapor? Hardly impressive, even if it was fully saturated with liquid water. As for carbon aerogel, you probably just looked at that claim on Wikipedia that carbon aerogel only transmits 3% of IR radiation -- as though transmission is independent of thickness ;) It's not really that impressive.

                The best way to deal with IR is mutlilayered reflective foil (reflection is always better than absorption, plus the

      • by DamonHD ( 794830 )

        I am sitting in my aerogel-drylined living room now.

        It's not quite as dramatic as you say, but two of us in here can easily maintain a 10C+ temperature differential from outside. (Wall U value now ~0.23W/Km^2.)

        http://www.earth.org.uk/superinsulating-our-living-room.html [earth.org.uk]

        Rgds

        Damon

        PS. With this and other measures we've roughly halved our heating demand, even in the teeth of the harshest winters in many years.

        • by DamonHD ( 794830 )

          Note: a (resting) person and a candle each give out about 100W in heat. So me + 1 candle would indeed keep this room comfortable now with a temperature outside of ~5C. The thermostat for the heating is set at 15C and is not turning on the heating, so room temperature is above 15C now.

  • New? What? (Score:2, Informative)

    by Anonymous Coward

    I have been playing with Aerogel capacitors for many years.

    I have a couple of 2.5V 50F units sitting on my desk right now. They are about the size of an AA battery. Pretty cool. They don't have quite the energy density of an alkaline battery but you can charge and discharge them much faster. Think of charging a rechargeable AA cell in about 30 seconds.

    Aerogel is not new. Their main weakness is their fragility. If you knock them around too much they break so for that reason they don't make great batter

    • The I am surprised we don't see them in Hybrid cars. Even pure EVs would benefit from ultra fast charging.

      • by fnj ( 64210 )

        Did you not hear the part about energy density? The 50F capacitor is described as having about the same size as an AA battery. An alkaline AA battery has the equivalent of several THOUSAND farads, and lithium ion significantly more. If your electric car can travel 50 miles now, then with the capacitors (probably costing millions of dollars) it would have a range of less than 1 mile.

        • by anethema ( 99553 )
          Ya the energy densite is worse than 'not quite' by a long margin.

          Just doing some napkin calcs here...

          2.5V 50F (and you usually shouldn't put em right at 2.5 volts but anyways) is about 156 joules.

          A NiMH battery is 1.2 volts 2.1WH is 9072 joules.

          Not even in the same order of magnitude.
        • I read this bit They are about the size of an AA battery. Pretty cool. They don't have quite the energy density of an alkaline battery as meaning their energy density was comparable to alkaline, but maybe I got that wrong. Too good to be true I suppose.

    • by Rei ( 128717 )

      One of my favorite things you could potentially do with aerogel is to make solid lighter-than-air structures. The best evacuated aerogels are about 20% lighter than air. Keeping them evacuated, of course, means sealing off their edges (aerogels are, unsurprisingly, gas-permeable), but the mass of such a seal rises proportional to the radius squared while the buoyant volume rises proportional to the volume cubed.

  • Dr. Zhai's faculty web page [ucf.edu] mentions conductivity and chemical sensitivity but not battery applications.

    Battery electrolytes need more properties than just being conductive.

    • by pspahn ( 1175617 )

      Wait, am I missing something? If the tubes are that much thinner, you can pack them in tighter, giving it gives more surface area, which is why it's better, right?

      I had been under the impression that was the main stumbling block in developing better batteries.

      • by Rei ( 128717 )

        What types of batteries are you thinking of? The main stumbling blocks in high-energy forms of traditional li-ion batteries are electrode pulverization during intercalation. Li-ion batteries with a lithium metal anode have difficulties with dendrite formation.

        How about other advanced batteries? Lithium-sulfur batteries have the stumbling blocks of polysulfide formation and migration across the membrane. Lithium-air batteries are limited by dendrite formation and electrode clogging. In fact, NAFION memb

  • by asm2750 ( 1124425 ) on Saturday March 05, 2011 @10:38PM (#35393816)
    From the TFA it looks like they did not make a working device yet. Still, sounds like an interesting application for aerogel. Hopefully it is safer, cheaper, and easier to make than lithium technology
  • They have at least one link missing the http:/// [http] prefix. FAIL
  • by Anonymous Coward

    One of the world's lightest solids, aerogel contains multi-walled carbon nanotubes (MWCNT) which each one several thousands thinner than human hair.

    Not lightest, but "least dense".
    Aerogel CAN (but doesn't have to) contain multi-walled carbon nanotubes.
    Which? Which what?
    Several thousands of what? Times? Or did you mean "thousandths"; again, thousandths of what?
    Than "a" human hair? Or just "human hair" generically?

  • I knew that the smoke that came out of electronics was important stuff. No wonder it stops working, all the energy has turned into a gaseous state.

  • Numbers please... (Score:5, Informative)

    by ls671 ( 1122017 ) * on Saturday March 05, 2011 @11:16PM (#35394024) Homepage

    As it is often the case with breaking news in battery related articles, I didn't find any numbers about the efficiency of this system in TFA. I would like to see a amazing break through in electricity storage but we have a long way to go still to match gasoline, so expect transportation prices to raise a lot as oil is slowly running out.

    Energy density:
    gasoline: 46.4 MJ/kg
    Lead Acid Battery: 0.14 MJ/kg

    http://wiki.xtronics.com/index.php/Energy_density [xtronics.com]
    http://en.wikipedia.org/wiki/Energy_density [wikipedia.org]

    Since accelerating the mass of the batteries raises the cost even further, batteries are even less efficient for urban transportation when you accelerate and decelerate a lot. We would need to bring back trolleys or another way not to have to transport the energy source for our cars to have something efficient.

    http://en.wikipedia.org/wiki/Trolleybus [wikipedia.org]

    • Even if aerogels really did make good batteries and had great energy density, you could end up like this:

      The Good News: New aerogel battery has highest energy density by mass than any other battery.

      The Bad News: Unfortunately, energy density by volume is so poor you'd need to fill your car with aerogel to make it a mile.

    • Accelerating the mass of the battery doesn't really matter. Induction motors can be run in reverse to recover most (>85%) of the energy put into the vehicle. The chemical storage in the battery is simply exchanged for kinetic storage in the vehicle. The problem is the increase in rolling friction on the tires, which increases with higher load, and is a significant amount of loss until you get well above highway speeds.
      • by ls671 ( 1122017 ) *

        Good point !

        I actually realized that I forgot to mention it right after posting.

        Unfortunately, recuperating the energy while braking has at most a 50% efficiency last time I looked, mainly due to heat dissipation occurring in the process. 85% seems optimistic depending of the real life setup you plan to use but you might be right after all ;-)

        It sounds to me like layers and layers of non-efficiency piled up together. At least if we compare it to gasoline efficiency. Trolley or other means of not having to

        • Unfortunately, recuperating the energy while braking has at most a 50% efficiency last time I looked, mainly due to heat dissipation occurring in the process. 85% seems optimistic depending of the real life setup you plan to use but you might be right after all ;-)

          50% seems awfully horrible for a generator. Induction motors tend to be above 90% efficient over most of their operating range, for both directions. The 85% value was a rough guess for the full power, plus recovery, including battery inefficiency. If I had to guess, I would say the 50% value was from the fact that most existing electric vehicles use pathetically small electric motors. The dynamic braking capacity of the 27kW motor in a Prius is extremely limited, meaning drivers typically fall back to m

    • To be fair it would be best to compare energy densities while compensating for the increased efficiency of electric motors over an ICE.

      Perhaps we need a new unit: km/kg. So if you have a vehicle which can travel 100km on 10kg of petrol the target would be a 10kg battery which can get the vehicle the same distance.

      Personally I don't see the need for equal petrol/electric vehicle ranges as the inconvenience of traveling to a designated refueling station is removed because there is electricity in my gar
      • by ls671 ( 1122017 ) *

        Good point for people living in rural areas. In urban or suburb areas, it doesn't really apply.

      • by fnj ( 64210 )

        The increase in efficiency of the electric motor over the internal combustion engine is (currently) in the neighborhood of 4:1 - 6:1, so instead of traveling 330 (46.4 / 0.14) times further on the same weight of "fuel," the former only travels around 50-80 times further. But no thinking person would use lead-acid batteries to try to replace gasoline - he would use lithium-ion or similar, which has 4-5 times better energy density, so you're down to a factor of 10-20. There is also regenerative braking for

  • by Giant Electronic Bra ( 1229876 ) on Saturday March 05, 2011 @11:25PM (#35394058)

    First of all aerogels are a whole class of materials. They aren't 'made from carbon nanotubes'. Obviously the aerogel they are working with contains carbon nanotubes, but aerogels can be made from MANY materials. You can make them from gelatin for that matter, though silica is the most common material (and what the highly insulating materials are generally based on).

    In terms of battery/capacitor applications those are pure speculation. Add to the long list of possible ultra-capacitor and/or super-battery concepts. You can hardly walk into a materials lab nowadays without bumping into some guy that has an idea for a super-battery made from X.

  • And in fact, it's likely that you have several in your home, in various electronic devices. Aerogel capacitors, (sometimes known as 'supercaps'), have been around for years:

    http://powerelectronics.com/portable_power_management/batteries/power_aerogel_capacitors_support/ [powerelectronics.com]

  • by wisebabo ( 638845 ) on Sunday March 06, 2011 @12:59AM (#35394412) Journal

    Since I'm hoping that this topic will be read by someone who actually knows something about aerogels, I'm wondering if they could comment on some crackpot ideas (mine not the researchers! ;)

    First, what is the "compression strength" of aerogels? (I'm not a material scientist so I don't know what is the proper term). If it is sufficiently high maybe it could withstand 1 atmosphere of pressure. In that case and if the aerogel structure was sufficiently light, imagine the following application: take a block of aerogel structure and wrap it in something like plastic wrap (non-gas permeable). Pump all the air out. Voila! It floats being lighter than air without using helium (costly) or hydrogen (flammable).

    The reason I said "aerogel structure" is because even if a SOLID block of aerogel is still too heavy (heavier than air), a "hollowed out" block or a block like the bones of a bird's wing could be significantly lighter. In a more extreme example, perhaps aerogel struts and girders could be used to make an ultra-ultra light structure that would be enclosed by the non-gas permeable film (how about using a 1-atom thick film of graphene? It has been shown capable of resisting an atmosphere's worth of pressure!).

    Secondly, how is this new (carbon nanotube based) aerogel made? Does it still require a super-critical fluid? If this (or any other aerogel) can be made in a vacuum (or if all the other materials needed for production can be recycled) perhaps it could be made IN ORBIT. Since aerogel is so light, just a "relatively" small amount of starting material (by mass) could make a large amount of aerogel (by volume). If 10 grams could make 1 cubic meter of the stuff, then 10 metric tons could make a piece 1 meter thick a kilometer square. Voila! The perfect "space garbage" collector.

    As demonstrated by the NASA space probe "Stardust", aerogels are very well suited for capturing hypervelocity particles; while the Stardust probe only collected microscopic particles its aerogel was very thin, a 1 meter thick aerogel would hopefully be capable of getting much larger (paint flecks? loose screws?) sized objects. While still capable of serious damage (in the right spot anything moving at 7km/sec can hurt) these small objects are not only much more numerous than the large ones but are the hardest (impossible?) to track and are economically infeasible to track down with a "space tug". Even if didn't completely stop them dead in their tracks, hopefully they would lose so much kinetic energy as to drop out of orbit quickly.

    Of course, these occasional impacts would gradually slow down the collector so it would need to be reboosted. A small but very efficient ion engine should do the trick which would also be used to go to a new orbit once it has "cleaned up" the one it is working on. Perhaps the best method would be just apply a very thin silvered film to one side and, by careful adjustments of its orientation, allow the sun's light pressure to blow it anywhere you want. (In fact if you apply crackpot idea number one, of aerogel "struts and girders" with crackpot idea numbet two, of the ability to manufacture this stuff in space and a very thin silvered film, you have the ability to make extremely large, low mass solar sails!)

    Of course both schemes also require the ability to make industrial sized quantities of the stuff, affordably!

  • Great. Another super battery. Will this one actually reach market or is it another steaming pile of nothing?

  • How would be named devices based on aerogel batteries? Vaporware?
  • The problem with virtually any battery system that is not based on using air as an oxidizer is the potential of explosion. The higher the energy density, the greater the explosion if discharged in an uncontrolled fashion. Indeed, TFA ends with:

    the multi-walled carbon nanotubes would allow huge amounts of energy discharged in short bursts.

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