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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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  • by Whuffo ( 1043790 ) on Monday February 08, 2010 @05:36PM (#31065446) Homepage Journal
    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.
  • Re:Problem with that (Score:2, Informative)

    by wizardforce ( 1005805 ) on Monday February 08, 2010 @05:48PM (#31065646) Journal

    The typical car battery is 12 volts with 6 cells linked in series with ~2 volt drop for each. Hardly the 200-300 volts that you're thinking are required. Even if a 200-300 voltage potential was required, you could take a low voltage source, convert to AC and step up the voltage with a transformer. Not that big of a deal.

  • by chinmay7 ( 776189 ) on Monday February 08, 2010 @05:54PM (#31065776) Homepage
    Why do I have to click through two blogs with fluff to reach the original article on PhysOrg? - http://www.physorg.com/news184585514.html [physorg.com]
  • Re:Good (Score:5, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @06:10PM (#31065990) Homepage

    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 [gas2.org]. 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.

  • Re:Can't Wait. (Score:3, Informative)

    by Adriax ( 746043 ) on Monday February 08, 2010 @06:24PM (#31066190)
  • by copponex ( 13876 ) on Monday February 08, 2010 @06:28PM (#31066244) Homepage

    Read the article. [imperial.ac.uk]

    Researchers from Imperial College London and their European partners, including Volvo Car Corporation, are developing a prototype material which can store and discharge electrical energy and which is also strong and lightweight enough to be used for car parts.

    Now, take your foot out of your mouth, and enjoy the following quote:

    "When men are most sure and arrogant they are commonly most mistaken, giving views to passion without that proper deliberation which alone can secure them from the grossest absurdities." -David Hume

    I'm living proof that slashdot is mostly full of arrogant people who enjoy misinformed and cynical deconstruction above all else.

  • Re:Problem with that (Score:4, Informative)

    by vlm ( 69642 ) on Monday February 08, 2010 @06:52PM (#31066574)

    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.

  • Re:Good (Score:3, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @07:03PM (#31066702) Homepage

    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.

    Oh, certainly -- your "gas station" has to be able to "average" the amount of power it feeds out, plus losses -- there's no way around that. Of course, running counter to this is that since the vast majority of charging is done at home (and to a lesser extent, work), you don't actually need that many rapid chargers nationwide. Most of the lower-end rapid chargers (~40kW is sort of the cutoff for what's considered rapid charging) don't typically use battery banks, and these are typically installed just one charger per location to spread the load around (although the charger may have multiple connectors on it; when two EVs are hooked up, each charges at half-rate). There are very few of the higher power rapid chargers out there right now, so it's hard to draw generalizations, but one would expect you'd average several per location to better take advantage of a common battery bank. Probably nothing like the 8-16 pumps at your typical gas station. Gas stations load so many pumps into each location because of the not inconsiderable expense of excavation to install the fuel tanks, plus fuel delivery costs.

    While studies suggest little to no need for new macro-scale infrastructure for mass adoption of EVs, there may be some local infrastructure improvements required, esp. if rapid charging for long, daytime EV trips takes off.

  • Re:Good (Score:5, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @07:11PM (#31066806) Homepage

    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.

  • Re:Good (Score:3, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @07:19PM (#31066908) Homepage

    Typically tanks of water, you anonymous coward. Exposed to air, your optimal fuel-producing species end up being attacked by predators and diluted by species that produce less (or no) fuel.

  • Re:Good (Score:4, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @07:30PM (#31067024) Homepage

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

    No, there isn't [gas2.org]. Not in a practical sense.

  • Re:Good (Score:5, Informative)

    by Rei ( 128717 ) on Monday February 08, 2010 @07:46PM (#31067136) Homepage

    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.

  • You don't get it. (Score:3, Informative)

    by gr8_phk ( 621180 ) on Monday February 08, 2010 @07:47PM (#31067138)
    You can't do shit with 12 volts. Hybrid cars use at least 150V, and electric cars (which I'm working on at this very moment) will be using 200-400V batteries (depends on the application). Voltage conversion is roughly 90-95 percent efficient, so throw away 10 percent of your range right there. However, we typically convert the high voltage down to run the low power stuff. If you wanted to do a 12V car and wanted to get 100kW you'd need over 8000 Amps DC. And yes, we're running motors around 110kW as traction motors plus or minus 30 percent (I'm not telling). One horsepower = 746 Watts, but I just figure 0.75kW.
  • BetterPlace (Score:3, Informative)

    by Cyberax ( 705495 ) on Monday February 08, 2010 @08:11PM (#31067334)

    BetterPlace (seriously, that's a company name) plans to do exactly this: http://www.betterplace.com/solution/charging/ [betterplace.com]

    They're planning to install battery swapping stations in Israel first.

  • Re:Good (Score:3, Informative)

    by Ungrounded Lightning ( 62228 ) on Monday February 08, 2010 @08:24PM (#31067454) Journal

    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.

    Look at Vanadium Redox batteries - where the battery is essentially a fuel cell sized for the power and would stay with the car, while the electrolyte is pumped through it from/to separate storage and the tankage is sized for the energy capacity.

    Swapping electrolyte on such a system would be quite practical. (And you could be credited for the state-of-charge of the partially depleted electrolyte you traded in.)

  • Re:Good (Score:4, Informative)

    by Anonymous Coward on Monday February 08, 2010 @09:42PM (#31067896)

    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)

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

    Convert capacitor to Joules
    Half of Farads multiplied by the square of Voltage

    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) [wikipedia.org]
    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.

Loose bits sink chips.