The rigid, rod-shaped Tobacco mosaic virus (TMV), which under an electron microscope looks like uncooked spaghetti, is a well-known and widespread plant virus that devastates tobacco, tomatoes, peppers, and other vegetation. But in the lab, engineers have discovered that they can harness the characteristics of TMV to build tiny components for the lithium ion batteries of the future. They can modify the TMV rods to bind perpendicularly to the metallic surface of a battery electrode and arrange the rods in intricate and orderly patterns on the electrode. Then, they coat the rods with a conductive thin film that acts as a current collector and finally the battery's active material that participates in the electrochemical reactions.
As a result, the researchers can greatly increase the electrode surface area and its capacity to store energy and enable fast charge/discharge times. TMV becomes inert during the manufacturing process; the resulting batteries do not transmit the virus. The new batteries, however, have up to a 10-fold increase in energy capacity over a standard lithium ion battery.
"The resulting batteries are a leap forward in many ways and will be ideal for use not only in small electronic devices but in novel applications that have been limited so far by the size of the required battery," said Ghodssi, director of the Institute for Systems Research and Herbert Rabin Professor of Electrical and Computer Engineering at the Clark School. "The technology that we have developed can be used to produce energy storage devices for integrated microsystems such as wireless sensors networks. These systems have to be really small in size--millimeter or sub-millimeter--so that they can be deployed in large numbers in remote environments for applications like homeland security, agriculture, environmental monitoring and more; to power these devices, equally small batteries are required, without compromising in performance."
TMV's nanostructure is the ideal size and shape to use as a template for building battery electrodes. Its self-replicating and self-assembling biological properties produce structures that are both intricate and orderly, which increases the power and storage capacity of the batteries that incorporate them. Because TMV can be programmed to bind directly to metal, the resulting components are lighter, stronger and less expensive than conventional parts.
Three distinct steps are involved in producing a TMV-based battery: modifying, propagating and preparing the TMV; processing the TMV to grow nanorods on a metal plate; and incorporating the nanorod-coated plates into finished batteries. It takes an interdisciplinary team of UM scientists and their students to make each step possible.
James Culver, a member of the Institute for Bioscience and Biotechnology and a professor in the Department of Plant Science and Landscape Architecture, and researcher Adam Brown had already developed genetic modifications to the TMV that enable it to be chemically coated with conductive metals. For this project they extract enough of the customized virus from just a few tobacco plants grown in the lab to synthesize hundreds of battery electrodes. The extracted TMV is then ready for the next step.
Scientists produce a forest of vertically aligned virus rods using a process developed by Culver's former Ph.D. student, Elizabeth Royston. A solution of TMV is applied to a metal electrode plate. The genetic modifications program one end of the rod shaped virus to attach to the plate. Next these viral forests are chemically coated with a conductive metal, mainly nickel. Other than its structure, no trace of the virus is present in the finished product, which cannot transmit a virus to either plants or animals. This process is patent-pending.
Ghodssi, materials science Ph.D. student Konstantinos Gerasopoulos, and former postdoctoral associate Matthew McCarthy (now a faculty member at Drexel University) have used this metal-coating technique to fabricate alkaline batteries with common techniques from the semiconductor industry such as photolithography and thin film deposition.
While the first generation of their devices used the nickel-coated viruses for the electrodes, work published earlier this year investigated the feasibility of structuring electrodes with the active material deposited on top of each nickel-coated nanorod, forming a core/shell nanocomposite where every TMV particle contains a conductive metal core and an active material shell. In collaboration with Chunsheng Wang, a professor in the Department of Chemical and Biomolecular Engineering, and his Ph.D. student Xilin Chen, the researchers have developed several techniques to form nanocomposites of silicon and titanium dioxide on the metalized TMV template. This architecture both stabilizes the fragile, active material coating and provides it with a direct connection to the battery electrode.
In the third and final step, Chen and Gerasopoulos assemble these electrodes into the experimental high-capacity lithium-ion batteries. Their capacity can be several times higher than that of bulk materials and in the case of silicon, higher than that of current commercial batteries.
A bonus: since the TMV binds metal directly onto the conductive surface as the structures are formed, no other binding or conducting agents are needed as in the traditional ink-casting technologies that are used for electrode fabrication.
"Our method is unique in that it involves direct fabrication of the electrode onto the current collector; this makes the battery's power higher, and its cycle life longer," said Wang.
The use of the TMV virus in fabricating batteries can be scaled up to meet industrial production needs. "The process is simple, inexpensive, and renewable," Culver adds. "On average, one acre of tobacco can produce approximately 2,100 pounds of leaf tissue, yielding approximately one pound of TMV per pound of infected leaves," he explains.
At the same time, very tiny microbatteries can be produced using this technology. "Our electrode synthesis technique, the high surface area of the TMV and the capability to pattern these materials using processes compatible with microfabrication enable the development of such miniaturized batteries," Gerasopoulos adds.
While the focus of this research team has long been on energy storage, the structural versatility of the TMV template allows its use in a variety of exciting applications. "This combination of bottom-up biological self-assembly and top-down manufacturing is not limited to battery development only," Ghodssi said. "One of our lab's ongoing projects is aiming at the development of explosive detection sensors using versions of the TMV that bind TNT selectively, increasing the sensitivity of the sensor. In parallel, we are collaborating with our colleagues at Drexel and MIT to construct surfaces that resemble the structure of plant leaves. These biomimetic structures can be used for basic scientific studies as well as the development of novel water-repellent surfaces and micro/nano scale heat pipes."
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TAz00
Graph in the video doesn't show much.
And 1 pound of TMV pr. acre seems awfully expensive, but I suggest you confiscate all current tobacco fields in the world, and just infect those.
fmfbrestel
Which means 2100 pounds of tmv, not 1 pound. 1 acre of infected tobacco = 1 ton of tmv.
fmfbrestel
gunslingor1
Increase surface area= higher capacity, lower charging time, more cycles, and less heat generation. Surface area is the most important factor in a battery, far more important than the dielectric.
Nanotubes have also been used to increase surface area by standing them vertically. These are all well established principles of battery tecnology. Yet, we still see zero consumer products... Why is battery technology being suppressed from the public?
With battery technology such as this, or the other nanotube version I described, a car such as the Nissan leaf, which currently gets 100 miles per charge, would now get 1000 miles per charge thus murdering the gas internal combustion engine for all eternity.
Do we see now why all these new battery patents are getting bought up by oil companies???
krundoloss
Is the Energizer bunny killing all the researchers? WE NEED BETTER BATTERIES! Why is everyone dragging their feet on this technology. Better batteries will save the world! Produce these things asap. But alas, it will not happen. Everyone is so careful and they have to do more research blah blah blah. Make them now! Put them in Electric cars, increase the power and range, then we wont need stupid fossils fuels anymore!
krundoloss
Eikka
Too bad it would take a full 5 days to recharge the battery out of a regular household socket.
Such a battery would hold 240 kWh of energy, which is practically impossible to quick-charge. No utility company would allow you to draw a megawatt of power without at least calling them in advance to let them know, so you don't black out the entire district.
Eikka
Ironically, if we really did that right now, or in the next 20 odd years, the extra demand for electricity would be covered by... you know what?
Fossil fuels.
It takes 3x the energy to produce 1x electricity, so you aren't actually saving anything.
krundoloss
fmfbrestel
What? um sorry, but even a coal fired power plant is MUCH more efficient then a car's internal combustion engine.
Lies, Damn Lies, Statistics.
fmfbrestel
Better batteries = big win for solar and wind. with 10x the capacity, the grid could start using plugged in cars for distributed electricity storage. This would make the unpredictable renewable generation much more cost competitive.
Just one way a better battery is good for everyone (except exon). There are many more, but its not my job to list them all.
Eikka
Nope. Save for combined generation, a coal plant's efficiency is about 37% and you also have to account for line losses to the customer, and conversion losses of about 15%.
The average thermodynamic efficiency of the electric car would be roughly 30%. Meanwhile, a Prius is between 26...35% efficient depending on how you drive it. If there is difference one way or the other, it's mostly irrelevant.
gunslingor1
-couldn't agree more.
-The grid tends to produce 50% less electricity at night, yet still only uses 10% of day values...i.e. plenty of power is currently being wasted to ground.
-Nuclear is the way to go, supported by tax credits for solar cells and other renewables.
-Not true man, ever hear of uranium? In addition, for vehicles, power density is just as important as efficiency. The best fossil cars use 25% of the energy in the fuel, electric is pushing 99.9% efficiency. Thus, an electric car with these batteries would drive 1000 miles where a fossil car would go 400 and, all in all, the electric would use less energy to do it.
The previous post from Eikka states faulty statistics, I'm a power E.E.
that_guy
Remember when we were waiting for the last wave of battery technology to come? My phone has a lithium Polymer battery in it. The technology does come to market, just with little fanfare.
Energizer is not holding back technology - It's that most of the new technology goes to the tech market first, where it's most cost effective. Why pay ten times more for a battery for your remote?
CHollman82
Hi,
Batteries do not produce energy... they merely store it.
gunslingor1
Techy handheld gadgets are not a concern of big oil, this is why they have been allowed to release somewhat new battery types. However, when you have a car that produces 100% torque, drives 3 times further, is 75% simpler (no transmission, catalitic converter, muffler, explosion protection, sparkplugs, carbon deposits, etc, etc, etc), costs 1/3 the amount to FILL up the tank, lasts infinitely longer (SOME electric motors can last 50 years with CONTINUOUS, not intermittent, operation).... what is an oil company to do?
Fossil fuels would have zero hope of competing.
Add on the fact that we can prevent 33% of all cancer deaths, for the people who don't already have it, and that is it, fossil is dead. Just to put that in perspective, 500,000 people die of cancer every year; we could prevent 150,000 of these deaths. Care accidents result in approx. 50,000 deaths each year, and think of how much money we spend to reduce this to 40,000... billions and billions...
CHollman82
Thrasymachus
Trim
gunslingor1
-No one is claiming that batteries produce energy. 25% of US energy is nuclear, ~10% hydro, and most of the rest is fossil of some sort. It would be a piece of cake to bump US nuclear up to 50% in 20 years. It needs to be done anyway. I think fossil supporters are becoming a really rare bread, unless of course they are being paid by the industry. Its just become an obsolete 100 year old technology, we've harnessed the power of the atom and we aren't that far away from harnessing the power of a star.
-Agreed 100%. That being said, scrubbers of certain chemicals like SO3 and NO3 can reduce these emissions massively, but only 5 out of hundreds of thousands of emissions chemicals are regultated,
Koen
Solar cells have the potential to become economical soon.
Skeptic_Heretic
Where'd you get this info?
gunslingor1
199% FALSE on the uranium shortage, but you COULD be right on the tokamak. This statistic may be off a bit, but the order of magnitude is all that matters at the moment:
The U.S. alone has, for relatively easy to mine unmined uranium, a 200 year supply. This is not considering the use of Uranium reprocessing which could expand this to 400-2,000 years depending on how many iterations of reprocessing are used. Add on Plutonium reactors and your talking 1-5,000 years supply. Then, create an avenue for nuclear disarmerment by using dilution of the explosive and reuse in reactors. we have plenty man.
Thanks Skeptic, good to see you.
gunslingor1
Fact of the matter, coal is far more valueable for the Uranium it contains that for burning, and it is no more difficult to extract than normal... hell, it's actually easier to extract. Not to mention in a coal plant, it goes straight into our air.
Oh yeah, and the Fusor thing I looked up. VERY INTERSTING! But MIT couldn't have stolen anything. The patent expired in 84 and I don't think a successful demo was ever developed... so the patent was invalid to begin with.
Skeptic_Heretic
gunslingor1
My newest project actually requires work =).
Javinator
This is the one of the biggest sources of available uranium in my mind. PWRs generally run on enriched (2-3% U-235 or something) uranium. The spent fuel is generally left with a U-235 content of 0.9-1.5% or something (going off memory... I know I'm not too far off if I'm wrong).
Natural uranium is 0.7% U-235 and there are power reactors burning this uranium all the time (D2O moderated). With some physical processing (expensive and hazardous, but less so than chemical processing), this used fuel can be used in these D2O moderated reactors (See DUPIC cycle for example).
As for plutonium, MOX fuel (mix of plutonium and enriched uranium) is already being burned in reactors around the world.
that_guy
Although energy companies are often part of the problem holding certain technologies back, I disagree with you that big energy is pulling the strings everywhere. More importantly, batteries do not create energy, and what you are saying has nothing to do with the conversation. The point is that lithium polymer was the "new" up and coming technology a few years ago, and it came as promised. Just as expected it was expensive and only cost effective for certain applications. No one is holding this technology back - You just think that making something new should be as cheap and easy as slapping a few two by fours together. Take your conspiracy theories elsewhere.
that_guy
Uranium is rare, period. You can level a mountain just to feed a reactor or two. That said, we aren't in any special danger of running out any time soon.
gunslingor1
-On planets with an iron core, uranium isn't as rare as you might think, though it is still rarer than gold. Atomic energy is INFINITELY greater than an equivalent mass of chemical energy. This is why a large coal fired unit will use upwards of 400,000,000 tons of fuel per year while a nuclear plant uses about 150 tons of fuel every TWO years. And you can't recycle fuel in a coal plant. My point is quantity in fuel is a factor that can be ignored, energy density is far more important.
-And FYI, they are currently leveling mountains for coal. Your average Kentucky mountain has 1 years worth of coal for a large power planet such as Paradise Fossil Plant.
-FYI, there has yet to be a site where uranium is mined via mountaintop removal; most are open pit and I'm pretty confident it'll stay that way for multiple millenia.
SomeOldFool
A better solution would be to give patent owners a reasonable period to demonstrate use or further development of acquired patents. If the patents have just been held or further development was unsuccessful, the patent should automatically be reassigned to the public domain so others could work on it without fear of patent troll attacks.
That would go far toward eliminating technology suppression and patent trolling. It would also help open up new technologies to people who actually want to develop and/or market them.
gunslingor1
-This is already in place, but I think its 14 years until the patent expires.
randomsrvapps
We need nuclear power no doubt about it our electricity grid is currently running at peak 24/7 and the voltage is supposed to be 240v and I have seen as low as 160v this year and I live right next to the damn power station!
And because of all the fluorescent lights now the power factor has been killed.