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Nanostructured Li-ion Batteries for Electric Cars
schliz writes "Researchers at the Delft University of Technology are developing nanostructured batteries that are expected to deliver more usage between charges, and shorter charge/discharge times, to mobile consumers within the next five years. The batteries will improve electric and hybrid vehicles, researchers say."
Battery technology will experience a sort of Moore's Law with the demand for hybrid and all-electric vehicles. This is just one of the first stories.
I'm always a bit skeptical of such items till I understand how likely it is to cause a fire in my garage while I'm sleeping or when accelerating away from a stop light. New tech is great, but means not a lot till tested in the real world.
With battery technology, the higher the density, the higher the chances of uncontrolled energy release. When it's safe and fairly cheap, then I'll be really interested.
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Will this patent monopoly on the new tech be used to kill it, just like NiMH batteries were prevented from powering cars by the car and oil corporations?
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batteries that are expected to deliver more usage between charges, and shorter charge/discharge times
I believe Sony has perfected the battery with the absolute fastest discharge time. I don't see how this can compete.
The theory of relativity doesn't work right in Arkansas.
it means that you can pull the energy out of the battery faster - "expected to deliver more usage between charges" would seem to indicate that actually the capacity is significantly increased.
It could mean that, but that isn't what is meant here. It can also mean that the battery can take in higher current during charge cycles and so reach the same state of charge sooner, and that the battery can release more current without failing or overheating due to its internal resistance, therefore making more energy available to the motors on demand - though yes, this latter capability does mean that the battery will be discharged sooner, given the same capacity battery, it is still better - because it can do what the old battery did (release at the old rate of charge) if that is what you want - but it can also give you more of a power surge for passing, towing, accelerating, getting out of (or into) trouble, etc.
Also, because a higher safe rate of discharge usually implies a lower internal resistance, it means that the battery wastes less energy when delivering current to a client device - the more internal resistance a battery has, the more heat is generated as a direct power loss, so most higher-current capable batteries tend to be a little better in this regard.
I've fallen off your lawn, and I can't get up.
Batteries have internal resistance which limits their current handling ability, so some types of batteries (NiMH for example) can not sustain currents of more than 2x the capacity of the battery (an 1800mAh NiMH AA battery shouldn't be discharged at more than ~3.6A). Higher current draw = higher battery temperatures = bad.
This also affects charging time, as you are again limited by battery temperature. You can't charge a battery in 1 minute at 50A because of the internal resistance of the battery. You CAN charge capacitors very quickly at very high currents, because their resistance is extremely low.
Lead Acid batteries?
They have good energy density and can deliver considerable voltage for their size, and we've been using them for a very long time. It seems to me that perhaps someone should try researching different formulas for the acid and the chemistry of the plates.
Sure, they're heavy and there's always the danger of a rupture but they are good at doing what batteries are supposed to do, storing and releasing electricity.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
Lead Acid Batteries must always be stored in a charged state. If the battery is left in a discharged state, a condition known as Sulfation occurs which makes charging the battery again difficult.
"Never try to tell everything you know. It may take too short a time."
Effectively it is about a 35AH battery with a total energy delivery of 12V * 35AH = 420WH. The equivalent LiIon batteries would weigh, I guess, around 4kg with packaging. As a result, lead acid batteries are unsuited to any automotive use except those where they can substitute for ballast, such as boats and powered wheelchairs where the batteries help lower the centre of gravity.
Quite a lot of research has gone into the lead/peroxide cycle, especially given the constant desire to make them smaller and more reliable. It hasn't been hugely successful. You can have high discharge rates and long life at the expense of much more weight and much higher cost, but the nature of the cycle itself (the production and destruction of large amounts of lead peroxide) makes it hard to design a system that can handle many charge/discharge cycles without very large and heavy storage arrays.
Pining for the fjords
It's a not too well known fact that, in the beginning, a lot of things *were* actually powered by electricity, *before* something else took it over. That something else wasn't necessarily better then the batteries they'd replace, but, sadly, history is full of examples where a less good alternative wins over the market (betamax vs VHS, anyone?). Somtimes electricity did win (it replaced gas for lightening homes/streets) but sometimes, alas, it didn't.
The same was true for cars. Many would think cars were always powered by diesel/petrol, but nothing is further from the truth. In fact, there were many fuels used to drive cars when they were first developped, and electricity-driven cars were actually a rather considerable percentage of cars. But then petrol came and took it over for reasons that are unclear (it has been speculated that it might had something to do with the sound, strangely enough; it made for a more impressing 'look at me, here I am!' - not unimportant to the late-victorian elite of that time. Heck, even today half of the gadgets are bought to show off (blu-ray, HD-DVD, anyone?). In that time, battery- or oildriven cars were in fact ahead of the petrol ones, but that rapidly changed the more popular the petrol-using cars became. In a few decades, the rest was all but gone.
If that hadn't happend, it is obvious we would be FAR ahead of our current state of developement where batteries and electricity-storage is concerned (just like petrol-injection has come a long way since the 19thy century). Just imagine the state of technology now on the same scale as petrol has improved, and all what we invent now (including the nano-tubes) would probably have been developed ages ago. It would have led to efficiencies and yields we can only dream of today. And also imagine the impact it would have had on other areas; a lot less - or none at all - CO2 from cars (and maybe the petrol-industry as a whole would not have reached the peak it has today) and all the problems associated with that would not exist (maybe even les wars)! (Arguably, one would - maybe - have had a environmental problems with acids and such, from the batteries; in that respect, vegetable oil would have been best, perhaps.)
It's funny (well...) to think how one little thing in our history can lead to such huge (and possibly devastating) consequences for humanity more then a century later.
--- "To pee or not to pee, that is the question." ---
...[electricity] produced by environmentally friendly means (IE not oil, not dams which destroy vast eco systems, not wind farms which kill birds) ...nor, say, solar cells, because most are sealed and won't allow poor spiders to nest in them?!?Watch out, your computer screen is surrounded by something called reality. Common-sense may come in handy should you chose to visit it sometime.
I agree partly, i give you that extracting the raw materials can be very harmful, but the energy required shouldn't be harmful. Still, we've thrown so much material away now, should we still be short on materials ? I think much money is to be made by 'harvesting' landfills.
Yes, I'm left. You have a problem with that?
Nanoscale Lithium battery technology leads me to think A123 cells. The cell from this startup are already on the market, powering handheld screwdrivers and model airplanes. They use a patented LiFePo4 reaction(or was there some sulfur in it too, dunno) and their process is much more ideal for automotive transport than NiMH(not enough energy density) or LiPo(Lithium polymer, it's what's making laptops go up in flames the last few years). LiPo has the highest energy density, but is very unsafe when punctured in a crash(or when overcharged): all energy in them will release in a short time, possibly causing fire as the decomposing polymer inside escapes as a flammable gas. The other drawback is that they have a very short lifespan: Max 500 charge-cycles (better count on 100-200) or 3 years (cells degenerate even when not in use). Thus far LiPo cells are prohibitively expensive, and no hybrid owner would like to fork over a few K every year for new batteries.
the A123 process is much more resilient wrt to abuse: you can run them down completely unlike LiPo or lead-acid, the stand overcharging much better, and if punctured they don't go up in flames. The company rates their cells as being able to deliver 2000 cycles, which is much more than lipo, NiMH, NiCad or Lead-acid.
And as far as I know, they have no ties to Delft University, but I have not read TFA yet...
They are here.
This space is intentionally staring blankly at you
Toshiba announced research on a technology for fast charging li-ions over two years ago. This was using nanotech materials for an improved anode (maybe cathode too), enabling fast charging (80% charge in one minute) and long life (99% capacity after 1,000 charges). A similar approach was also annouced, about the same time, by Altair Technologys in Reno. It's all about increasing the effective surface area of the anode, and perhaps making it from stronger stuff.
In traditional Li-ion cells, a big wear factor is that the anode can form a parasitic battery with the electrical contact, causing the terminal to eventually wear out, faster as you approach full cycling the battery. Heat is also a factor, in both terminals and the full cell... the higher internal resistance of the Li-ion vs. NiMH (or better still, NiCAD) limits peak power, and also increases the risk of damage or, particularly in quesitonably made cells, explosions.
Dramatic improvements in both of these are necessary to enable practical (in a commerical sense) pure electric vehicles (BEV). There's no conspiracy necessary... traditional NiMH cells are a problem for full electrics.. which the actual reason none of these cars have been successful. Not to mention the expense... the Toyota EV-RAV4, for example, cost $42,000 and gave you about 100 miles on a charge.. and that with Toyota still selling them at a loss (as they did in the early days of the Prius, too).
In a hybrid, the batteries are only partially cycled (my 2003 Prius runs the NiMH cells over 40% of their capacity range; Toyota extended this to about 60% on the models starting in 2004), and that keeps them very long lived. Natrually, better batteries make a better hybrid, but the fact my Toyota can only go about 2-3 miles on a full charge doesn't impact its general use; the issues around battery technology today make the BEV a small niche product.
But the energy density is just too low even full cycling NiMH to make a BEV with mass appeal... most people would demand at least 200-300 miles of range, charging times on-the-road similar to that of petrol fueling (not the minimum of 15-30 minutes you'll have with today's cells), and long life (full cycling NiMH, they're good for about 500-1000 charges).
Once you have a higher density cell that doesn't wear out and can be charged in under 5 minutes, full EVs will be practical enough for a mainstream automaker to POSSIBLY launch a full production car, not just an experiment. This is critical technology for improving hybrids as well, and keep in mind that all practical FCEVs will also be hybrids (fuel cells suck at peak power demands, they like to be slow and steady, so you need a battery or supercapacitor to enable the peaks).
-Dave Haynie
If the car is fully electric it requires A LOT of new infrastructure (which is especially problematic in big open spaces where caves are more common than your "modern world")
If the car is a hybrid it's simply less efficient than diesel at the moment. Advances in battery power will improve efficiency, but it will not remove the need for petrol.
I see nothing wrong with electric cars, but with the current state of technology +5 years is not going to bring about a revolution, hence my irritation of this [false] advertisement. It's just a lot of hype about nothing of consequence and everyone joins in the "Hi Ho, it's off to greener earth we go".
As for the "tailpipe" argument, I fully acknowledge your point of view and the proof behind it. I do not, however, believe that building the necessary infrastructure for this is feasible in the foreseeable future (read my life time). Not all of us live in big cities and/or "modern world" countries. It takes 5 years to design a power plant, let alone build it and the supporting infrastructure and agree with all the relevant parties who/what the said plant will be supporting. A car manufacturer is simply not going to make something for less than 10% of it's customer base unless it's a PR stunt or it has money to burn.
Take a reasonably developed country like Russia. It has huge CO2 production, there's no way in hell you'd get anyone there to use an electric car. In USA where people drive to their neighbours, you still have vast distances to cover. A car that has 300 mile range and takes 2 hours to charge is not feasible. Who will buy this car? City dwellers? Where is the need? Most of the people I know in cities don't own a car... How will the charge time reduce? Make a hybrid, charge it with petrol and we've gone full circle.
In closing I'd like to state that in a perfect world I would love it if we would start building the said infrastructure for electric powered [everything] using the most up to date and efficient technology available at the time. Be it nuclear, solar, wind, geothermal or gravity as long as it's renewable. But we don't live in a perfect world and it takes a long time to take theory and put it into practice.
Of course no one really cares about reality and just wants to get on the environmentally high horse and pipe on about electric cars. Show me some news about something actually practical, like someone developing a way for people to stop commuting to work.
Let's assume an average cruising consumption of about 15kw for a small car. At 60mph with a 300 mile range, that's 75kwh. To charge those cells in 5 minutes, assuming an 80% efficiency, will need 75 * 12 * 1.25 =~ 1.1 Megawatts. At 440V, even with a 3-phase charger, that's over 1000 amps. At 11KV it's a more reasonable 100A, but the weight of the inverter gear and the shielded connector in the car is considerable and you are going to spend rather more than 5 minutes padlocking the interlocks and cross checking before and after charge. At 440V the main issue will be the weight of the cables. Three cores of around 400mm cross section each are rather heavy.
It's possible to imagine a world in which fuel stations supply exchange cells, but given the natural nervousness of most drivers when close to empty, it's unlikely to be practical or cost effective.
The model is wrong. You have to imagine a world in which car parks have charging stations that charge at reasonable rates, as do hotels and houses. You will need a general beefing up of the electricity distribution network, and you will need plenty of nuclear, solar and wind energy sources. And people will have to plan maybe a little further ahead than they do at present. Long trips will mandate an overnight stop. Probably a good thing as the only accidents I have ever had were after driving too long in a day.
On that model with a more reasonable 10-hour charge, the necessary charging rate is about 9KW - still a heavy cable, but with a socket about the size and complexity of the sort used for portable machines in factories and for boat shorepower.
Just don't try to use your wind turbine. In our location, to run my small car on its current, fairly low usage cycle, I would need a 6M diameter turbine on a 40M pylon, and I suspect the neighbours would object.
Pining for the fjords
I have to disagree with your leading statement. The energy density of lithium-ion batteries today is adequate for making practical electric cars. Of course more is always better, and I'm optimistic that it can be improved further -- but energy density is no longer the big sticking point that it was.
The little two-seat Tesla Roadster with a 250-mile range has been demonstrated, and multiple companies are now working on more practical four-door cars which can have a 200-mile driving range. This doesn't require any breakthroughs, and it will get you "to the next town" with very few exceptions.
The critical areas that need improvement are cost and service life. Tesla Motors are projecting a life span of five years or 100,000 miles for their carefully managed battery pack. That's much better than the two years you stated. I think with the research that is ongoing, service life will further improve over the next several years. (And GM are betting on this happening to make their Chevy Volt concept workable.)
I think the requirement that cars be "refueled quickly" is overstated. The longer the range becomes, the less you need to refuel or recharge it quickly. With a dependable 200-mile driving range between charges, and the ability to recharge overnight at home, most people won't need to stop at a charging station mid-trip all that often. If you can get the range up to about 500 miles, then rapid charging would become moot for the great majority of people. (At least speaking for myself, I don't think I've ever driven more than 300 miles in a day's time, and I wouldn't want to drive more than 500 in a day if I could possibly avoid it.)
I have looked into flywheel storage technology. It looked promising several years ago, but battery technology advanced faster and has left flywheels behind. Notable problems you have with flywheels are: energy density, energy losses while the flywheel is spinning idle, and safety concerns about its failure modes.
Nothing... unless you live near a mine or a smelter.
http://www.semissourian.com/story/1195543.html
Enivornmentally freindly? I guess so if it's not in your backyard.
Quick and dirty rebuttal. . . .
1. fast recharge isn't needed if driving range becomes long enough (say 300 to 500 miles)
2. electric cars pollute much less than gasoline cars, due to their energy efficiency
3. tens of millions of electrics can be charged using off-peak power without building any new power plants
4. http://www.youtube.com/watch?v=u5kkU23bfEc
Firefly Energy is building foam-core lead-acid batteries that claims to have energy densities as high as current generation NiMH batteries at much less weight and at 1/10th the cost.
Dog is my co-pilot.