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New Material Transforms Car Bodies Into Batteries

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."

37 of 213 comments (clear)

  1. Can't Wait. by cohensh · · Score: 5, Funny

    I can imagine it would make a multi-car pile up quite exciting. Just another effort to make real life more like a Michael Bay movie.

  2. Another wonderful fantasy by Whuffo · · Score: 5, Informative

    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.

    1. Re:Another wonderful fantasy by jollyreaper · · Score: 4, Interesting

      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.

      --
      Kwisatz Haderach
      Sell the spice to CHOAM
      This Mahdi took Shaddam's Throne
  3. Re:Good by maxume · · Score: 5, Funny

    You just need to learn how to be a leader.

    --
    Nerd rage is the funniest rage.
  4. Re:The new material? DiHydrogen Monoxide by dfsmith · · Score: 3, Funny

    Are you crazy? Dihydrogen monoxide kills over 4000 people a year in the US alone!

  5. Re:Good by Rei · · Score: 5, Interesting

    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).

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  6. Re:The new material? DiHydrogen Monoxide by nicknamenotavailable · · Score: 3, Funny

    Are you crazy? Dihydrogen monoxide kills over 4000 people a year in the US alone!

    Replace the 'dihydrogen monoxide' with 'hydroxyethane'.
    It might not improve things, but it seems like more fun.

  7. Slashdot does it again! by TimHunter · · Score: 5, Funny

    Once again, in less than 30 minutes the Slashdot crowd finds multiple fatal flaws in the results of years of work by highly-trained educated people. And frequently without even bothering to RTFA! Is there nothing we can't do?

    NOBODY expects the Slashdot Community! The chief weapon of the Slashdot Community is presumption...presumption and arrogance...arrogance and presumption.... Our *two* weapons are presumption and arrogance...and cynicism.... Our *three* weapons are presumption, arrogance, and cynicism...and an overweening sense of entitlement.... Our *four*...no.... *Amongst* our weapons... Amongst our weaponry...are such elements as arrogance, presumption...I'll come in again.

    1. Re:Slashdot does it again! by Monkeedude1212 · · Score: 4, Insightful

      Is there nothing we can't do?

      Find a date for Valentines day?

    2. Re:Slashdot does it again! by Anonymous Coward · · Score: 5, Funny

      This year it's February 14.

      Thank you, thank you.

    3. Re:Slashdot does it again! by Jeng · · Score: 4, Insightful

      You remember the story about someone wanting to power a car off of hydrogen that is produced by burning magnesium in water?

      Some ideas are just so stupid that they are put on the main page for us to poop on them.

      Why is this one stupid?

      Cost is first, this is built on top of carbon fiber which is already pretty damn expensive without also turning it into a battery. Yea, one day they may bring the cost down, but it is not in the reasonable future.

      Kaboom is second. Its not just about energy storage, its about where you store the energy. With electric powered cars and petrol powered cars the energy is stored in a safe spot in the car, the body of the car is about as unsafe as you can get.

      --
      Don't know something? Look it up. Still don't know? Then ask.
  8. Link to original article by chinmay7 · · Score: 3, Informative

    Why do I have to click through two blogs with fluff to reach the original article on PhysOrg? - http://www.physorg.com/news184585514.html

  9. neat idea by wizardforce · · Score: 3, Interesting

    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.

    --
    Sigs are too short to say anything truly profound so read the above post instead.
  10. Re:Good by Rei · · Score: 5, Insightful

    Biofuels are not a long-term solution. Corn ethanol is over two orders of magnitude more land-intensive than solar thermal. Algae is just under one order of magnitude more land intensive. Plus, biofuel creation requires water, fertilizer, processing, etc. And the combination of needing "lots of water" and "lots of sun" can be rather mutually exclusive, as the sunniest places in the country are desert. Solar thermal is closed loop.

    If your goal is to turn solar energy into propulsion, pure electric is the way to go.

    Although the long recharge time is part of it

    That's what rapid charging is for.

    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.

    Indeed, the real issue is price. But that will fall significantly with mass production. And the operating cost advantage will remain, so eventually, even if sticker shock remains an issue for prospective buyers, seeing a lease price that's significantly cheaper than a gasoline car's lease plus the cost of gasoline that month should eventually drive the point home.

    Furthermore, the main point to oversized gas tanks is to make it so that you don't have to fill up too often in your daily lives. Filling up is, after all, a pain; who wants to drive out of their way to pay for the privilege of pumping carcinogens in the middle of a blizzard? One of your average EV driver's favorite benefits is the fact that you start each day with a full charge. You don't even have to think about it in your daily life. The only time range comes into play is when you take long trips. But what's the point of having 700-800 miles on a long trip? Dear god, if you drive 700-800 miles without stopping to rest or eat, please don't do it when I'm on the road!

    Lastly: In 1989, a new top of the line battery hit the market: the nickel metal hydride cell. It boasted 45Wh/kg energy density. Today, just over two decades later, commercially available li-ion cells boast up to 220 Wh/kg -- almost five times higher -- plus an order of magnitude higher power density. This trend shows no signs of slowing down; rather, it appears to be accelerating. So take that into account when talking about range for the future.

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  11. Re:Good by Architect_sasyr · · Score: 3, Insightful

    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.

    Grazing costs almost nothing. The infrastructure is already in place for pasture and oats, and most horses can pull a cart just fine. The aw-toe-mo-beel will fill a nice, and that is all.

    Sometimes, for no reason at all (!!), some things just become huge. The car was reliant on reliable and obtainable fuel, and roads, and the world dealt with them just fine - I don't see why, when the option becomes viable and enough of the group-think follows it, electric cars will not follow the way of their predecessors.

    --
    Me failed English...
    FreeBSD over Linux. If my comments seem odd, this may explain...
  12. REAL link to original article by argent · · Score: 4, Informative
  13. Re:Good by Rei · · Score: 4, Informative

    There is also the issue of having an electrical grid that can handle that. Charging a battery in minutes with enough power to get you hundreds of miles takes a non-trivial amount of power, no matter how good your battery is.

    You don't draw it from the grid. You draw it from a battery bank. The battery bank is in turn trickle-charged from the grid.

    And in case anyone's curious, yes, they do make extremely high power chargers. TARDEC got one last year that does 800kW. I don't know how much that one cost, but ones in the ~250kW range are typically ~$125k-ish (and about the size of a vending machine). That may sound like a lot, but then again, a gas station generally costs $1-2m to build, and you have to pay for tear-down at end of life (tearing down a charger is a net gain, from scrap). Plus, expect prices to fall over time.

    Chargers that big generally require that their connectors or even their cables be cooled. Which makes me wonder when we'll see the next logical step in that evolution -- having the charger provide coolant for the battery pack instead of the EV providing it. After all, why make the EV haul around a powerful cooling system when your charger already has one and is already bringing coolant all the way to the vehicle? All the vehicle should need is a connector for the coolant and ducting for it to travel through. If you use something like supercritical CO2 as a coolant, you won't even have to worry about coolant contamination or residual coolant being left over in the system.

    The current fast-charging pseudo-standard, TESCO, doesn't do that, though. But in the future, I expect we'll ultimately see it.

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  14. Re:Good by mweather · · Score: 4, Insightful

    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.

    Why not just make the batteries swappable at service stations? Then the only range that matters is the distance to the next service station.

  15. It's a capcitor! by reg106 · · Score: 4, Interesting

    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.

  16. Re:Good by c6gunner · · Score: 3, Insightful

    As the electric parts of the car were responsible for said fire, it seems resonable that electric cars will burst into flames more often than gas burning cars. Therefore, it can be logically deduced that electric cars will result in much more smoke than the fossil fueled alternatives.

    In what universe?

    My microwave oven leaked and caused me to be exposed to some radiation. As the microwave oven was responsible for the radiation, it seems reasonable that houses with microwave ovens will release more radiation than houses with thermonuclear reactors. Therefore, it can be logically deduced that we should all use nuclear reactors to cook dinner. Ipso facto, etc, etc.

    Look on the bright side: your train of logic has done an amazing job of demonstrating the "garbage, in garbage out" principle.

  17. Re:Good by Anonymous Coward · · Score: 3, Funny

    Algae is just under one order of magnitude more land intensive.

    Algae grow in water, you fucking moron.

  18. Re:Good by vlm · · Score: 3, Insightful

    You don't draw it from the grid. You draw it from a battery bank. The battery bank is in turn trickle-charged from the grid.

    The problem is, a typical gas nozzle runs about a megawatt. Theres 20 of them at my local quickie-mart or whatever its called. Sometimes all are in use. Often half are in use. Even in the middle of the night at least one is in use. "Trickle Charge" is still going to be a couple megawatts, and in an area without that kind of service.

    I admit the whole "fast charging" thing is pretty bogus. The furthest I've ever driven in one day was 500 miles and it was a torturous living hell. I dream of having a car that can't do that, so I have the perfectly socially acceptable excuse that my car simply can not go 500 miles per day. What a darn shame I'll be unable to sit in my car for 8 hours. Drat. Boo F-ing Hoo Hoo.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  19. Re:The new material? DiHydrogen Monoxide by Hognoxious · · Score: 4, Funny

    Dihydrogen monoxide is a gateway drug. Most adults who are addicted to hydroxethane drank DHMO when they were children.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
  20. Re:Good by Jeng · · Score: 5, Insightful

    Why not just make the batteries swappable at service stations?

    Too many variables. How much charge is in the current battery, how much wear and tear are in the battery you just got versus what you just gave, what happens when you get a partial dud, how many batteries can be swapped out a day, the physical labor of swapping batteries, what do you charge/how do you come to the cost and how does that make you competitive with your competition.

    I thought it would be a smart idea to change out the electrolyte instead of the whole battery, but it wasn't actually all that smart either.

    --
    Don't know something? Look it up. Still don't know? Then ask.
  21. Bonus by HangingChad · · Score: 4, Funny

    Researchers are currently developing a new auto body material that can store and release electrical energy like a battery.

    And it would make the neighbor's dog peeing on my car a pay-per-view moment.

    --
    That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
  22. Re:Problem with that by vlm · · Score: 3, Informative

    Hardly the 200-300 volts that you're thinking are required.

    He's anthropomorphizing it when he writes "Car batteries want to be 200 to 300 volts".

    Real engineers know you can gin up a set of equations to optimize an overall system. Not surprisingly, an electric cars optimum voltage and current end up suspiciously nearby, yet somewhat below, industrial heavy equipment and diesel electric traction motors of the same power rating. Lower it a bit because the power levels are a bit lower (plenty of 3000 HP locomotives, not many 3000 HP electric cars... yet). Also lower it a bit because insulation requirements are a bit stricter for morons. Lower it a bit for temperature derating, run the car in death valley, etc. Also lower it a bit for battery reliability, plates shorting, vibration etc. You end up in the 300ish volt range for "car power levels"

    Similarly, your average electric motorcycle should be happy around 60 volts. Which is suspiciously close to where they seem to be.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  23. Re:Good by Jeng · · Score: 3, Interesting

    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.
    http://en.wikipedia.org/wiki/Ethanol#Cellulosic_ethanol

    Bio-diesel will probably be bigger than ethanol though.

    --
    Don't know something? Look it up. Still don't know? Then ask.
  24. Re:Good by Rei · · Score: 4, Informative

    I mentioned the worst and the best. Do I really need to spell out all of the midpoints?

    Cellulosic ethanol is estimated at up to 1,500 gallons/acre/year. At 30mpg, that's 45,000 miles/acre/year.

    Ausra's proposed 177MW Carrizo solar thermal plant was to be situated on 640 acres. That's 277kW/acre. Assuming a capacity factor of about 0.3 (clear skies, heliostat), that's about 727,000,000 Wh/acre/year. At 250Wh/mi, that's ~2,900,000 miles/acre/year.

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  25. Re:Good by couchslug · · Score: 3, Insightful

    That would lock in permanent battery form-factors in the infancy of car development where we should not commit ourselves.

    --
    "This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
  26. Re:Good by Smooth+and+Shiny · · Score: 3, Funny

    He can't lead in a Prius. Seriously... it can barely keep up with itself, let alone other traffic.

  27. Re:Good by Rei · · Score: 3, Informative

    there is a limited supply of Lithium and other elements used in these batteries.

    No, there isn't. Not in a practical sense.

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  28. Re:Good by Rei · · Score: 4, Informative

    What really matters is what the resulting cost is.

    1) Land use absolutely *does* matter. As does water use, fertilizer use, etc. It matters for wildlife habitat (incl. rainforest), for food production, for algal blooms, for countless things.

    2) From a cost perspective, solar thermal wins there, too. EVs are really cheap to run. Even if cellulosic ethanol could manage to sell for the same price as gasoline (and note that 30mpg ethanol is notably better than 30mpg gasoline, in the above calculations) -- say, $3/gal -- it would be 10 cents per mile. Even if you had to pay 20 cents per kWh for the solar thermal (most next-gen solar thermal is predicting less than that), rather than the US national average for electricity of 10 cents per kWh residential (and notably less for industrial power), that would be five cents per mile.

    --
    I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
  29. Re:Good by gyrogeerloose · · Score: 5, Funny

    Cellulosic butanol is way more exciting than cellulosic ethanol.

    Fuckin' A! Whenever anyone even mentions cellulosic butanol I can barely contain my enthusiasm! ;-)

    --
    This ain't rocket surgery.
  30. Re:Good by Skal+Tura · · Score: 3, Interesting

    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

  31. Re:Good by Anonymous Coward · · Score: 4, Informative

    Dear god, if you drive 700-800 miles without stopping to rest or eat, please don't do it when I'm on the road!

    I'm sure some semi-truck drivers have done it. For us regular drivers, who stop and rest after 350 miles, will the car be recharged in 12 hours? That depends on how standardized, and available charging is. The average motel today probably would bill extra, if it were even possible (big parking lots, no outlets, etc.) or if unattended charging was allowed.

    But, I'm not trying to be a kill-joy. I'd love to have an electric car or motorcycle with a range of between 40 and 80 miles. I'm an electronics engineer, so I'd even have fun building my own solar and wind power to charge it.

    On that note, I've recently done some comparisons between rechargeable batteries and capacitors.
    To summarize: batteries win with normal approaches (low cost and complexity), but high voltage capacitors have the best performance and greater usable energy capacity. Technically capacitors should outlast batteries. And, in theory, a high voltage capacitor is simpler to build than either a supercap or battery, so the cost could be lower in mass production.

    I used the SI unit Joules, instead of Wh, because it's easier to visually compare numbers greater than 1, as opposed to using enginnering notation for milli, micro, nano, and pico.
    The following information doesn't take into account usable energy, because that's dependent on how the things are used. A capacitor will outperform a battery in high current usage. Capacitors can also be totally discharged to 0V without being damaged and batteries cannot (most battery Ah ratings take that into account).

    Convert Watt-hours to Watt-seconds (Joules)
    E=W*3600

    Convert battery to Joules
    The product of voltage V, amp hours Ah and 60 squared, is Joules E (watts per second)
    E=V*A*3600

    Convert capacitor to Joules
    Half of Farads multiplied by the square of Voltage
    E=0.5*F*V^2

    Fun math:
    One Kilowatt Hour is 3.6MJ (3,600,000J, 1000Wh*3600)
    A single AA NiMH is 10.4KJ (10,368J)
    A L-ion 3.7V 4Ah is 53.28KJ (53,280J)
    A 16V, 100F capacitor is 12.8KJ (12,800J)
    A 12V 40Ah battery is 1.728MJ (1,728,000J) (Two 12V 40Ah batteries are nearly 1KWh, 3.456MJ)
    A (real) 6.5KV, 9500uF capacitor is 200.7KJ (200,700J) ~ a 1x1x2 foot sized industrial capacitor
    A (theoretical) 26KV, 9500uF capacitor is 3.2MJ (3,200,000J)
    A (theoretical) 300KV, 1000uF capacitor is 90MJ (90,000,000J, 25KWh)

    All the capacitors are physically bulkier than batteries, typically twice the size or worse for a given amount of Joules.

    Recently pulled from wikipedia
    http://en.wikipedia.org/wiki/Battery_(electricity)
    Secondary Battery Chemistries
    NiCd 1.2V 0.14 MJ/Kg
    Lead Acid 2.1V 0.14 MJ/Kg (0.1232 MJ/Kg, found for real battery)
    NiMH 1.2V 0.36 MJ/Kg
    NiZn 1.6V 0.36 MJ/Kg
    L-ion 3.6V 0.46 MJ/Kg (0.635 MJ/Kg, found for real battery)
    *Zinc-Air 1.55 1.35-1.65 MJ/Kg
    (*electrical or mechanical recharging is possible)

    Aluminum-Air is similar to Zinc-Air, but I don't much have information on it.

    Interesting bit of information about capacitors (as battery substitutes)
    A 1V, 2F capacitor is 1J (Linear)
    A 2V, 1F capacitor is 2J (Exponential)
    A 1V, 10F capacitor is 5J (L)
    A 1V, 20F capacitor is 10J (L)
    A 10V, 1F capacitor is 50J (E)
    A 20V, 1F capacitor is 200J (E)
    High voltage capacitors are capable of storing more energy than high farad capacitors. Because an increase in voltage is an exponential increase in energy, and an increase in farads is a linear increase in energy.
    Supercaps are safer to work near, cheaper, and physically smaller (but heavier) than high voltage capacitors. Unless I'm mistaken, the highest voltage capacitor type is a vacuum capacitor (vacuum is the dielectric) hence it being potentially more lightweight than any other type of capacitor.

  32. Re:Good by Anonymous Coward · · Score: 5, Interesting

    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.

  33. Re:Good by crispytwo · · Score: 3, Funny

    All we need are two brushes on the bottom, and a slot to put the car in

    voilà, no batteries needed!

    woot!