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Nanotech Anode Promises 10X Battery Life
UNIMurph sends word out of Stanford University that researchers have discovered a way to increase battery life tenfold by using silicon nanowires. Quoting News.com: 'It's not a small improvement,' [lead researcher Yi] Cui said. 'It's a revolutionary development.' Citing a research paper they wrote, published in Nature Nanotechnology, Cui said the increased battery capacity was made possible though a new type of anode that utilizes silicon nanowires. Traditional lithium ion batteries use graphite as the anode. This limits the amount of lithium — which holds the charge — that can be held in the anode, and it therefore limits battery life... 'We are working on scaling up and evaluating the cost of our technology,' Cui said. 'There are no roadblocks for either of these.'"
No , please, stop right there. Here, let me put it into perspective for you:
http://en.wikipedia.org/wiki/Image:World_energy_usage_width_chart.svg
For those too lazy to follow the link.
World energy consumption:
Oil: 37%
Coal: 25%
Gas: 23%
Nuclear: 6%
Biomass: 4%
Hydro: 3%
Solar heat: 0.5%
Wind: 0.3%
Geothermal: 0.2%
Biofuels: 0.2%
Photovoltaics: 0.02%
WORLDWIDE photovoltaic production is about 13GW. A single nuclear reactor or coal fired powerplant can produce 1-2 GW. Solar couldn't even power a tiny european country with populations of a few millions. Let alone China, India, the US, Russia etc
The most probable ways to reduce CO2 emissions from our energy generation are:
-Carbon capture and storage
-Expanding Nuclear power
-Increased use of Gas in place of Coal ( gas contains a lot of hydrogen and hence emits less CO2 per kwH than does coal ).
Ironically these are all measures which are fiercely opposed by Greenpeace et al, who instead want us to hope that wind and solar will save the day. At present production wind, solar and solar heat taken together produce about 0.82% of worldwide energy. To avoid a 2 C increase in global average temperature we need substantial cuts in CO2 emissions before 2050. Does anybody SERIOUSLY believe that photovoltaic / wind is up to the job?
I mean for the love of god, electric cars are great in that they could let us use Nuclear power or plants equipped with carbon capture technology, but they will not be solar powered. Not within the foreseeable future at least.
Since when does "what we have now" imply "what we'll have with the radical technology improvements that are presently occurring"? You do realize that not only are solar thermal prices dropping, but there have been some *major* advancements in the economics of photovoltaic systems. Silicon cells are typically profitable to sell at $4/W (and are currently selling at $5/W because of supply shortages). CIGS cells are profitable at $1/W. This is a major, major leap that'd make solar cheaper than coal almost everywhere in the world.
Let's look at Nanosolar as an example. Their first plant, when at full capacity, will make them one of the biggest solar producers in the world (430 MW/year if I recall correctly). But this is just their first plant. Selling cells that are profitable at $1/W at nearly $5/W means they'll be profiting hand over fist, which means that investors will fight for the chance to throw money at them. How long do you think it'll take them to scale up with essentially unlimited venture capital? I'm betting not very long. They built their current facility with $100M raised just a year and a half ago, and they've already delivered their first product. Given that most of that money had to go toward simply commercializing their laboratory-scale process, what sort of capacity do you think they could pull off with, say, the next $1B in cash? Dozens of GW/year? And Nanosolar is just one CIGS manufacturer among many. And there's CdTe, too. Unmet demand begs for a market solution. It's inevitable that it's going to be filled.
Longer term, here's a crazy new tech for you to chew on: nanoantenna solar cells. A completely different process than conventional cells, which use photons to knock electrons off a donor, these new cells are simply designed to receive solar energy in the same way that a larger antenna receives the several-orders-of-magnitude-longer wave radio signals. They should be able to be produced on a cheap reel-to-reel process like CIGS cells, yet they have the potential to be as much as 80% efficient, even receiving the infrared that the Earth emits at night.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
It's not even 10fold -- at least not currently. It's only "several" times improvement without an equivalent cathode improvement. Now, that may well happen, but it hasn't happened yet. However, they think they may be able to commercialize it in five years.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
And, let me add, I don't say this to diminish the importance of this news. A severalfold improvement is major, major news. Not in the least because this anode likely lends itself to very rapid charging at the same time. What we're looking at is, as it stands, giving it the sort of charge time and range as a gasoline vehicle, meaning that there's no reason to stick with gasoline (when you can get lower maintenance (assuming long lifespan batteries), higher torque, quieter, more thermodynamically efficient vehicles that only require gas station visits on long trips, require hardly any new infrastructure (versus oil, which needs a lot of infrastructure construction) due to mostly off-peak charging (timer-based to get you a low rate and use our huge amount of unused off-peak capacity), lets us use domestic energy supplies instead of funding our enemies with oil imports, and even if all of the electricity came from burning fossil fuels, would still emit almost half the greenhouse gasses. An equivalent cathode improvement for electric vehicles simply means that you could then drive cross-country on a single charge.
As for lifespan, Yi Cui's team expects to be able to get at least 1,000 cycles out of this. That may not sound like much, but when you can go ~350 miles on a charge, that's 350,000 miles. And not like the battery just disintegrates up at the end of its lifespan; it simply doesn't hold as much charge.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
This technology sounds wonderful. I'd absolutely adore batteries to last ten times longer than they do at present. It would be amazing... imagine 20 or 30 hours of 'real life' battery life on a laptop instead of 2-3 hours. However, I'm really getting tired of stories on Slashdot that basically can be summarised as "Scientists promise [amazing product] using [amazing technology]". Nanotech, nuclear fusion, genetic engineering, micro-scale fission power plants, exotic materials... whatever. You know what? I'm sick of reading stories about theoretically possible things that might (but probably won't) make it into an actual product some time in the near future.
Slashdot ought to have a section for "navel-gazing scientific speculation". Seriously, this sort of "we can make [x] perform [10, 100, 1000...] times better!" bullshit belongs right alongside the "in [10, 20, 50] years, everyone will be in flying cars!" type of crap which has filled Scientific American for, well, forever.
It's 2008. We still don't have flying cars, practical nuclear fusion, fission-powered cars, or multi-petabyte holographic storage devices. In the real world, advances in technology are usually incremental and evolutionary in nature, or a serious tradeoff at best (As an example, the move underway from platter-based hard drives to solid-state hard drives, while revolutionary in nature, involves massive tradeoffs in price-per-gigabyte which are only slowly lessening). It took CD technology a decade or two to give way to a successor with 10 times the storage capacity (dual-layer DVD-R), and making bits smaller is (arguably) a lot easier than increasing energy density (barring the use of nuclear technology or other exotic things which-- again-- isn't realistically going to happen any time soon).
So where's the "NotGonnaHappen" tag?
With spending like this, exactly what are "conservatives" conserving?
First of all, Nanosolar HOPES to make the cells at $1/W, they are nowhere near that cheap yet, and this is the price their marketing department HOPES to achieve. Secondly, that is the price for the cells without factoring in energy storage devices, energy conversion systems, servicing etc
With most of nuclear reactors built in the west ending their licensing in about 2030 - 2040, Oil running low and gas prices rising due to low demand, it seems likely that nations will turn to coal. This effectively implies you will either have to do carbon capture and storage or start building nuclear plants very soon unless you want to have your greenhouse gas emissions rocket due to massive deployments of coal plants. To think that solar will replace Coal, Oil, Gas AND nuclear within 30-40 years amidst the east rapidly increasing the energy intensity of their economies, is wishful thinking at best.
But no, we're going to gamble on some hypothetical solar breakthrough. Despite the fact that no realistic way to overcome the problems with intermittent supply, that they don't produce energy at night, diffuse and limited output, as well as the high price, having been demonstrated. If you think the press release about what one heavily subsidized solar company "hopes to achieve" negates any of my arguments, then I'd say you are naive at best.
As for nano-antenna solar cells, again, you are talking several decades of development at the very least. They won't save us from the energy gap that is likely to occur within 20-30 years, and they only deal with the costs incurred by the cells themselves, they don't address the cost of storing and converting the energy.
First of all, Nanosolar HOPES to make the cells at $1/W, they are nowhere near that cheap yet, and this is the price their marketing department HOPES to achieve.
And your information comes from? Nowhere, that's where, because they're not sold on the open market yet, so claims like "they are nowhere near that cheap yet" are complete BS. All of their capacity is currently going to a German municipal plant. Secondly, all of the CIGS companies are giving numbers in the same ballpark, as are the CdTe companies.
Secondly, that is the price for the cells without factoring in energy storage devices, energy conversion systems, servicing etc
Duh. That's part of a general solar economics calculation. Only an idiot would just multiply $1/W times the desired number of watts. A large, batteryless installation in Anchorage, AK of nanosolar cells gets a 30 year IRR of 7-8%. In Las Vegas, it's more like 13-14%.
Thirdly, it is the price under optimal conditions, with perfectly aligned cells. (and on, and on...)
(Dragnet theme)Duh, duh duh duh. Duh, duh duh duh, duh!(/Dragnet theme)
Do you think we're idiots? What's next? "Third, the cells only produce power when the sun is visible. Fourth, you need to have wires to conduct the power. Fifth, you need "humans", who can use the power...."
They are also relying on indium, an element which is thought to become scarce due to increasing demand, and of course, mass-deployment of indium based solar cells would certainly push the price up.
Indium is more common than silver, is easier to recover than silver (because of its close interrelationship with zinc ores), and CIGS cells use a miniscule amount of it (nanoscale-thickness coatings). Indium's current high price is more related to a lack of demand for it before LCD TVs started using it in bulk; this led to a few of the world's only indium recovery circuits shutting down without new circuits replacing them at other mines. It's not a problem. It only takes a few years to ramp up production.
Finally, even if they were able to start producing these at competitive costs and at a large rate, you still have the problem that you will have to increase solar photovoltaic output by a factor of 1000 just to reach 20% of current energy demand.
Huh? Did you ignore my post, above, where it already addressed this?
With most of nuclear reactors built in the west ending their licensing in about 2030 - 2040, Oil running low and gas prices rising due to low demand
Whaa? For one, nuclear is making a serious comeback in the US. Two, oil is not running low. Light sweet crude is, but light sweet crude != world petroleum production capability. Venezuelan super heavy crude and Canadian bitumen syncrude are taking off. Third, the demand for gasoline has been rising constantly year to year. Are you confusing the annual demand fluctuations with year to year growth in consumption? Demand is always lowest in the winter, highest in the summer.
[quote]But no, we're going to gamble on some hypothetical solar breakthrough.[/quote]
Hypothetical? Yeah, about two dozen companies, some of which have been selling them in smaller volume for years, is "hypothetical". What's next -- are CFLs hypothetical as well?
[quote]Despite the fact that no realistic way to overcome the problems with intermittent supply, that they don't produce energy at night, diffuse and limited output, as well as the high price, having been demonstrated.[/quote]
In the pacific northwest, and to a lesser degree the west coast as a whole, energy storage is a non-issue. The west relies a lot on hydro power, and hydro pairs perfectly with solar (it already has a low capacity factor, so there's no additional economic cost to the hydro producers). Even in the east, solar alone with no storage can eliminate the p
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
First of all, Nanosolar HOPES to make the cells at $1/W, they are nowhere near that cheap yet, and this is the price their marketing department HOPES to achieve
....at.... drumroll please..... 90 cents per watt.
Minor information injection here:
Nanosolar _is_ making solar 'sheets' now... no wishful thinking involved.
They've contracted with a German company who has ordered roughly 600 megawatts worth of sheets
The sheets will be mounted in panels in a factory near Berlin, and used in Germany, which because of favorable laws requiring utilities to buy back power from customers, is experiencing a HUGE demand for renewable energy sources for the homeowner.
giving it the sort of charge time and range as a gasoline vehicle
Stop and think for a second, or do some math, because electric cars will *never* 'fill up' as fast as a chemically powered car. Instead of pouring in gasoline, imagine that gasoline powering a flamethrower which you point into your gas tank, and you'll have a better grasp of what it means to transfer energy directly (as in electricity) versus high density potential (like gas).
Assume your electric car needs only 20 horsepower to maintain 60 mph.
One horsepower is about 750 watts, assuming perfect efficiency.
That's 15 kilowatts to keep the car going 60 mph.
To make the numbers easy, figure 300 mile range. That means you need to drive for 5 hours.
5 hours times 15 kilowatts is 75 kilowatt-hours.
Now let's assume the 'electric station' supplies electricity to charge your car at 500 volts.
75000 watt-hours divided by 500 volts equals 150 amps.
For an hour. Assuming perfect charging.
To get to a 3 minute charge time (one twentieth of an hour) you need 20x the amperage, or 3000 amps.
To carry 3000 amps of current for 3 minutes without melting insulation, my numbers show you'd need copper wire about 2.5 inches in diameter (and you'd still get a temperature rise of 90 degrees farenheit over ambient). And note to electricians who may think the numbers are off, don't forget you're charging with DC voltage, not AC, so you're gonna need about 5000 circular mils worth of wire.
I cannot imagine Joe Average plugging TWO wires, each of which is thicker than his wrist, into his car for a 3 minute recharge.
And yeah, you could drop it to 300 amps, but then you're talking 5000 volts.
So basically... you're never, ever going to see a 'gas station' for electric cars. They'll always be charged for long periods at home, or at 'charging garages'.
Maybe you take the wrong approach to "charge" a car.
What about standard, pre-charged batteries that you simply swap at the "gas" station instead of really charging the car? This way the whole process can be done in the same amount of time than filling up gasoline.
This is not even to complicated. You more or less rent the battery from the respective company and return it when it's empty (just to exchange it for a fully charged one).
The "gas" station has all the time in the world to charge the empty batteries, replace/repair faulty ones, etc.
Isn't that a more logical (and much safer) solution to the problem?
Your numbers are a bit off. The Tesla roadster quotes a range of 356km on 54kWh.
If you use 1000 V , 4 parallel plugs, a 100A charging current, that gives you 66kWh in 10 minutes. 100A is doable with AWG 1 ( 7.35mm ), and most of the time you wouldn't be charging from empty anyway, so something like 6 minutes is more reasonable. Of course, this is only necessary if you need to take a pit stop during a long journey, most people would probably just charge it at home over night.
Who cares if things get reported more than once. It's something that enough people thought was interesting that they thought it should be posted. Obviously some people want to discuss it. If you've already read the story, and don't want to discuss it any more, then that's fine, but there's lots of people who miss the story the first time around, and would like to discuss it.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.