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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."
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.
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.
You just need to learn how to be a leader.
Nerd rage is the funniest rage.
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!
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.
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!
Physorg is a tarpit. Here's the REAL original article.
http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_5-2-2010-10-26-39
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!
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.
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.
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."
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.
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
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!
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!
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.
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.
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.