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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 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!
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
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.
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.