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Power Transportation Hardware

New Material Transforms Car Bodies Into Batteries 213

MikeChino writes "As battery manufacturers race to produce more efficient lithium-ion batteries for electric vehicles, some scientists are looking to make the cars themselves a power source. Researchers are currently developing a new auto body material that can store and release electrical energy like a battery. Once perfected, scientists hope the substance will replace standard car bodies, making vehicles up to 15 percent lighter and significantly extending the range of electric vehicles."
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New Material Transforms Car Bodies Into Batteries

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  • Re:Good (Score:2, Interesting)

    by Jeng ( 926980 ) on Monday February 08, 2010 @05:50PM (#31065684)

    Even once they do perfect the electric car I would imagine there is no getting rid of the internal combustion engine.

    Diesel powered vehicles will slowly turn to bio-diesel options and gasoline powered engines will slowly turn to ethanol power.

    Electric is good for basic commuting where the route will be basically the same day after day, it is not good for if you do not know how far you will drive a day. Although the long recharge time is part of it, the main part is that you do not want to buy more battery than you are going to be using since the battery will be one of the most expensive parts of the car.

    A larger gas tank costs almost nothing. The infrastructure is already in place for bio-diesel and ethanol and most cars can be converted. Electric cars will fill a niche, and that is all.

  • Re:Good (Score:5, Interesting)

    by Rei ( 128717 ) on Monday February 08, 2010 @05:50PM (#31065692) Homepage

    I really hope we get this electric car thing figured out soon because I am just about sick of following smoke belching vehicles every day.

    The tech is here. Modern batteries can rapid charge in minutes (given adequate cooling) and yield hundreds of miles of range. The issue is cost. For most EVs, battery packs are generally limited in size by price, not volume or weight. And not just battery cost that's the problem; quality AC drivetrains are expensive as heck right now. You can't even use a lot of mass-produced accessories with EVs if the conventional accessory requires a gasoline engine to be running. The good news is that it's all about volume. Your typical LFP or manganese li-ion pack combined with an AC drivetrain uses almost no rare or expensive raw materials. You have lithium salts ($4-8/kg), phosphoric acid (in the case of LFP), iron powder, a porous plastic membrane, graphite, etc in the battery pack; your motor optimally uses copper windings, but can also use aluminum; the inverter also uses copper or aluminum, plus things like silicon carbide for thyristors; etc. The expenses are primarily the huge amounts of labor and capital costs per unit because of very low volumes and because of the lack of production process refinement.

    BTW, the article summary is wrong (and partly the article, too). What they're talking about is not a battery; it's a capacitor. Which means that even if the whole body is made of the stuff, it's not going to be enough energy capacity for reasonable range. Plus, you have to consider how it'll change your vehicle's weight, structural strength, etc. There is always a cost-benefit analysis to consider.

    Still, it could potentially be useful for making less-critical structural elements (say, the bellypan) to use for buffering (rather than energy storage).

  • neat idea (Score:4, Interesting)

    by wizardforce ( 1005805 ) on Monday February 08, 2010 @05:58PM (#31065840) Journal

    The idea is a very interesting one and the problem isn't so much the risk of electrical shock (done correctly there isn't one) but the cost of the material and the ease to which the material can be replaced if it ever fails. With normal car batteries, replacing them is easy. Just unhook the +/-
    from the battery and lift it out. With the car body acting as a battery, if something fails, the entire material must be removed. This sounds to me to be fairly expensive as well as having to replace the material which its self may have a fairly significant cost. Over time that will be less the case but the problem of replacing a faulty "battery" remains.

  • by jollyreaper ( 513215 ) on Monday February 08, 2010 @06:06PM (#31065940)

    According to TFA their plan is to make the body panels act as one plate of a huge capacitor. I can't even begin to list all the technical flaws in their proposal; just reading it made my head hurt. They really should run their promotional pieces past a real engineer before spreading them all over the net.

    I have visions of car crashes involving brilliant blue flashes and passengers exploding from the sudden discharge of electricity. Then again, we're already driving around in steel coffins filled with gallons of explosively flammable liquid so there's not much left to lose.

  • It's a capcitor! (Score:5, Interesting)

    by reg106 ( 256893 ) on Monday February 08, 2010 @06:26PM (#31066220)
    The device is a capacitor that can also support mechanical load. The first hint is that they call it energy storage, but never actually call it a battery (though it may "replace a battery"). In the linked video, they are using a custom device (indicated by the Imperial College in the upper left), that is also labeled as capacitor charge-discharge indicator. The storage device appears to be two sheets of carbon fiber mesh held together with a "multifunctional resin", i.e. a nonconductive material with a high dielectric constant that is also capable of supporting a large mechanical load (or rather, binding to the carbon fiber so that it supports a large mechanical load, i.e. a composite). The idea of using ultracapacitors to replace batteries has been around for a long while. Ultracapactiors usually use esoteric materials and have problems with leakage over long periods of time, but have met with success in some applications. The military has funded a lot of research for ultracapacitors to replace batteries for the electronics on missiles, an ideal application since missiles potentially sit on the shelf for years, and then need to function precisely for a very short period of time. (the cap would be charged as part of the launch procedure.)

    In the example mentioned in the video (GPS case made of the material), I'm not sure why it would reduce wiring, since the capacitor would still need to be charged, just as if it were being fed by the cars electrical system. I suspect there are some real advances in the work, but the interesting features don't come through in this video for public consumption.
  • Re:Good (Score:3, Interesting)

    by obarthelemy ( 160321 ) on Monday February 08, 2010 @06:45PM (#31066482)

    You're overlooking 2 things:

    1- for daily commutes, you start each day with a full battery, which is more convenient than having to do regular trips to the service station.

    2- for longer trips, batteries could be swappable, making longer trips possible with not much more pain than currently. that means
    2a- coming up with an easy and standard way to do it (government regulation may be helpful, if it can prevent market fragmentation), and
    2b- re-thinking ownership, because people will be leery of swapping their brand new battery for someone else's clunker. A yearly battery lease may be the way to go. It would alleviate the battery price problem, too.

  • Re:Good (Score:3, Interesting)

    by Jeng ( 926980 ) on Monday February 08, 2010 @06:53PM (#31066590)

    Corn ethanol is over two orders of magnitude more land-intensive than solar thermal.

    You'll make your point better if you don't bring up the worst possible case. Corn ethanol is only done for political purposes because it makes no economical sense.

    Ethanol from cellulose based waste looks promising. Always good when a waste stream can be turned into a productive product. []

    Bio-diesel will probably be bigger than ethanol though.

  • by Anonymous Coward on Monday February 08, 2010 @06:58PM (#31066644)

    Except that despite what hollywood would have you believe, gasoline is not actually explosive unless it is vaporized (which it will do at room temperature, but the gasoline would have to be spread out in order for enough to vaporize in order to explode)

    A capacitor holding enough electricity to power a car getting shorted would certainly create a nice explosion though.

  • by Rei ( 128717 ) on Monday February 08, 2010 @08:18PM (#31067404) Homepage

    Ugh, don't get me started on bumpers. My (now) wife got into a 5mph accident that caused $3k worth of damage to our car. She hit a jacked up pickup that was still within the legal range; his bumper wasn't even close to ours. His trailer hitch cut right through the hood and engine compartment.

    It's unfathomable to me that we mandate bumpers but don't require that they meet up.

  • Re:Good (Score:4, Interesting)

    by Skal Tura ( 595728 ) on Monday February 08, 2010 @08:24PM (#31067450) Homepage

    Li-Ion isn't even the best, LiPo can deliver more per Kg, and higher peaks without voltage drop off, thus being the #1 choice for RC models. Altho, they are restrictively expensive, hazardous to handle, can't take temperature variations and only lasts for couple of years.

    As for Biofuels: There's methods to use WASTE for making biofuel, they are doing that here in Finland, and sell 85% bio-ethanol, 15% gasoline fuel, made from biowaste. Downside is it's not as energy dense, thus you consume more along with the fact that many gaskets can't use them. The plus-side is that an engine designed for biofuel can have better compression (or higher boost pressure), burns very clean, and smaller engines can be made more powerfull due to the ethanol compression characteristics.

    Biofuel made from waste solely is not taxing to the environment, quite the contrary, and does not require extra landmass. Algae based can use waste aswell.

    Growing corn etc. for biofuels is the stupidest thing ever. Also, corn is far from the best to use for it. It's just that the corn industry is so large, so much supply, but not enough demand, they have to keep it afloat somehow.

    Also, the land mass etc. problems for biofuels is just propaganda. Biofuels can be made in small areas aswell, and when waste is used as the source, there's no problem with it. Besides, water is plenty... This planet is mostly water afterll

  • Re:Good (Score:2, Interesting)

    by mysidia ( 191772 ) on Monday February 08, 2010 @08:28PM (#31067482)

    Uh, we should want them locked in as soon as possible.

    New form factors can be developed, as long as they get standardized.

    It's car manufacturers that want proprietary formats, so they can charge a boatload for proprietary replacement parts (VS pennies for commodity replacement parts).

    It's like saying "Let's not lock-in computer ABIs or processor specs in the infancy of OS development" (today, in 2010)

    Better to stick with proprietary OS APIs and proprietary network libraries, so users have to buy software specifically licensed against this computer's spec.

    And so hardware manufacturers can make a boatload selling the only OS that will work with their hardware, or selling the only hardware that will work with their OS (rather)

    E.g. HPUX good, Linux bad.

    Ultrix/NonStop OS good, VxWorks bad.

    Mac OS good, DOS bad.

    AIX good, BSD bad.

    OSF/1 good, SysV bad.

    NeXTSTEP good, Windows bad.

    iPhone OS good, ChromeOS bad.

    Atari DOS good, BeOS bad.

  • Re:Good (Score:1, Interesting)

    by Anonymous Coward on Monday February 08, 2010 @09:21PM (#31067768)

    That could backfire. I usually slow down if some asshole is riding my tail and beeping me.

    Then again, I make it a point to take good care of my car, so I'm not the smoke-belching car driver that GP is talking about. They might behave differently..

  • Re:Good (Score:5, Interesting)

    by Anonymous Coward on Monday February 08, 2010 @10:46PM (#31068200)

    Thanks for mentioning solar thermal energy instead of photovoltaics.

    One other solution that has not been considered is the use of solar thermal energy to synthesize gasoline and diesel fuel from carbon dioxide. Sandia is working on it with their "CR5 thermochemical engine". It's estimated at 150,000 gallons/acre/year of REAL, drop in replacement GASOLINE - not ethanol, not diesel. At 24 MPG (U.S. average), 3,600,000 miles/acre/year. It is clear that thermochemical engines will beat biofuels in efficiency.

    Of course, the real question is cost and rare element usage. No one likes to talk about that.

  • Re:Good (Score:2, Interesting)

    by Eclipse-now ( 987359 ) on Tuesday February 09, 2010 @12:34AM (#31068788) Homepage
    No no no! These are not real objections when the company sells you the car, but maintains ownership of the battery! "Physical labor" of swapping batteries? Are you serious? Don't tell me you haven't seen the Better Place battery swap automated station? []

    It sounds like you need to spend some time here. [] Just like in the "olden days" the King's messenger didn't wait overnight for the horses to rest & recharge their 'batteries', but swapped them out, Better Place has come up with the battery standards that are so good Tokyo is trialling TAXIS out on this Battery-swap system, and they'll NEVER get a chance to just sit still and charge for 8 hours! I can't believe there are slashdotters that don't know about Better Place, especially when HSBC just invested $350 million in Better Place and the CEO is all over "The Economist" podcast. They're coming to San Francisco, Hawaii, Tokyo, Canberra... and at a price / km at about half the price of oil, it's simply going to CHANGE THE WORLD people!
  • Re:Good (Score:3, Interesting)

    by TheRaven64 ( 641858 ) on Tuesday February 09, 2010 @09:34AM (#31071130) Journal
    Note, however, that the land just needs to be somewhere where there is sunlight, it does not need to be good farmland. There is lots of desert space in the middle of the USA that would be ideal for algae farms but terrible for farming conventional crops.
  • Re:Good (Score:1, Interesting)

    by Anonymous Coward on Tuesday February 09, 2010 @03:29PM (#31076434)

    Aluminum-air batteries right now are about 4.68 MJ/kg. The theoretical energy density limit of aluminum is 30 MJ/kg. Zinc's limit 5 MJ/kg. Aluminum-air is not rechargeable, but refuelable, kindof like a fuel-cell. The aluminum-air fuel cell is 1000 times cheaper than the hydrogen fuel cell.

    It's not exponential, it's energy = 1/2*C*V^2. The voltage is limited by the breakdown voltage. Silica and teflon are the highest breakdown voltages I've seen.

  • Re:Good (Score:3, Interesting)

    by Rei ( 128717 ) on Tuesday February 09, 2010 @06:37PM (#31079242) Homepage

    You are actually getting %50 sunlight to hydrogen efficiency at a 0.3 capacity factor with those engines

    That sounds about right.

    The Mobil M syngas to gasoline (also called methanol to gasoline), is %86 percent energy efficient

    That sounds about right as well. And then there's the difference in electricity/gasoline to kinetic energy efficiency for the vehicles themselves.

    1kW/m^2 * 1 acre * 1 year = 127,706,349 megajoules.

    As I mentioned in my last post, it doesn't work that way. Take a look at what solar farms actually look like up close []. Notice all the empty space on the grounds? You have to space them out or they'll shadow each other at any point other than noon and you will have spent a lot of money on hardware that's being used suboptimally. There's also roads and other wasted land. So if you're calculating based on solar input, you need to multiply not just by capacity factor, but a spacing factor as well. Or, conversely, if you want to assume full shadowing, you can't just use the numbers from an existing solar thermal plant; you'll need to calculate that one from 1kW/m^2 as well.

    Probably the easiest way is just to compare the efficiencies. Solar thermal plants will generally get you somewhere between 30% and 50% generation efficiency, depending on the tech used (the latter case being the high temperature molten salt plants). Electric motors + inverters will generally get you somewhere in the range of 85-90% average efficiency. Li-ion packs are very efficient (96-99%). Transmission in the US averages 92.8% efficiency. I'm not sure what sort of distribution losses you'd have for your fuel -- I'd wager somewhere along the order of 5-10%. Gasoline engines operate in the mid-30s percent efficiency in peak conditions, but only average about 20% in typical driving conditions. So, putting it all together, you get 23-41% system efficiency vs. ~8% system efficiency. So overall, the gasoline comes off a bit better in the calculations than my first impression, but obviously it's not going to beat out just using electricity.

    Still, there is potential if they can do it affordably. That's a heck of a lot more land efficient than biofuels, even algae, and probably cheaper than algae too (the tankage requirements kill it for algae). Still, the hardware costs seem bound to be a lot higher than for solar thermal electricity costs, just judging from a manufacturing complexity perspective.

    Also, Rei, are you an energy researcher or something??? You make a lot of really good comments here on /. about energy.

    I work in the EV industry, so it's part of my job to stay on top of various battery and fuel technologies. :) My company develops software to provide accurate range calculation to vehicles (including terrain, weather forecasts, etc). While we launched it for EVs since they have particular need for it, it can work with any kind of powertrain, present or future (unless the laws of physics up and change on us!), so I need to stay on top of things. Also, my father works in the oil industry (he's actually the CEO of one of the US's largest refiners), so I get diverse perspectives.

  • Re:Good (Score:3, Interesting)

    by Rei ( 128717 ) on Tuesday February 09, 2010 @07:45PM (#31080048) Homepage

    High school? I never would have guessed. And usually it's glaringly obvious. :)

    That's cool that you work in the EV industry. That must be some accurate software to include weather forecasts in vehicle range.

    Oh, it has to be! :) Weather -- in particular, temperature -- plays a very large role in EV range. For example, as Lutz recently noted, while he had been getting 40+ miles on his Volt in city driving warmer weather, during Michigan's recent cold snap, it got only 28 miles. We download and parse NWS forecasts (GFS MOS MAV, GFS MOS MEX), then interpolate between them (both geographically and temporally).

    It's a neat field :)

    I'm a homeschool highschool student who reads about these matters for fun. I experiment, unsuccessfully, with attempts to build batteries.

    I'm curious as to what exactly you mean by this. Are you building battery packs or individual cells? If battery packs, what kind of cells are you using? And if building cells, what chemistry? I'm curious how high-tech you're going -- I assume somewhere between "potato battery" and "lithium ion" ;).

    Have you heard of LISICON membranes? They're really neat. They let you use an aqueous electrolyte on one side and an organic on the other while still allowing lithium ions to cross. Plus, they're resistant to dendrite damage if you use a metallic lithium anode (when metallic lithium plates, it tends to form dendrites which can pierce traditional membranes). LISICON membranes are used in Li-air and nickel-lithium cells.

    Lithium-sulfur cathodes are also pretty cool. A team from the University of Waterloo had a really clever approach to . They wicked molten sulfur into the pores of mesoporous carbon, then functionalized the surface with polyethylene glycol. This keeps the lithium polysulfides, which tend to be soluble and escape the cathode, trapped inside the pores (they're hydrophobic). They got some really amazing results. The paper is "A highly ordered nanostructured carbon-sulphur cathode for lithium-sulphur batteries". Again, like with li-air and nickel-lithium, probably a wee bit outside of one's capability to build at home -- but still neat. :)

    One of the craziest concepts I've run into is that of a "digital quantum battery" (actually capacitor). The paper is a bit dense, but basically, the idea is to print an array of nanoscale vacuum-tube capacitors (lithographically, like with computer chips). When you get that small, quantum effects help keep current from arcing, so they can run them up to huge voltages (by capacitor standards, at least). The electric fields can be made so intense that you can put so much mechanical strain on the electrodes that one needs to be made out of a carbon nanotube for optimal performance. :) And of course, it'd be all nontoxic and have pretty much limitless cycle life.

    Modern battery research is pretty fascinating. While the odds of any one tech panning out are low, the odds of every battery tech not panning out are almost nil. Did you know that some of the li-ion batteries starting to hit the market now have silicon anodes instead of graphite? This is brand new, as of January. So forget everything you ever heard about the maximum theoretical energy density for li-ion batteries. Silicon ups it significantly; it can hold as much as 10 times more lithium in the anode.

    Even if you're just building battery packs, rather than individual cells, there's a lot that can be done there. I've been tempted myself to mess around with that. In my "ideal" charging setup, cells are separated by a corrugated aluminum foil that acts as a heat sink, with forced air being able to be blown through the channels for cooling. For extreme rapid charging, I'd have the charger itself provide coolant, with the charger cable being actively cooled by the coolant it provides to the vehicle. Coolant would be supercritical CO2, due to its low viscosity

Things are not as simple as they seems at first. - Edward Thorp