Nanotech Anode Promises 10X Battery Life 193
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.'"
Good deal (Score:3, Interesting)
Re:Good deal (Score:5, Interesting)
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 [inl.gov]. 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.
Re:But will it explode 10X more powerful ? (Score:4, Interesting)
Anyway, poorly manufactured Lithium batteries are dangerous because they ignite easily. It has very little to do with their energy content.
Re:Dupe (Score:5, Interesting)
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.
Re:Good deal (Score:3, Interesting)
The IEA PV trends report from 2003 estimated 20% growth a year for the next decade, but has since been revised upwards. Current trend is looking more like 25% growth in area produced year, which gives somewhat more than that in power generated because average efficiencies are climbing (allbeit slowly).
Furthermore, increased awareness and interest in global warming is likely to lead to increased incentives and consumer-interest, so I personally think the trend is more likely to grow rather than stall. My guess would be 30% growth a year for the next decade, which is aproximately double your estimate. This is also ignoring HEAT from the sun, which is currently at about half a percent of our energy-needs and *also* growing rapidly.
Still, you're right: Neither solar nor any other renewable can singlehandedly solve the problem in the next 20 years timeframe. They can contribute, particularily when many and diverse ones are used, but they can't alone solve the problem.
Proven tech can do a lot though. Did you know that if USA where as efficient measured in GDP/Energy-consumed as Sweden is, you'd be consuming -half- the energy you currently do ? That's not rocket science, that's what Sweden does -TODAY- (and Sweden is improving too!)
We're going to need more than -one- answer; if it was easy, it woulda been done a long time ago.
Re:Am I the only one getting sick of this? (Score:2, Interesting)
Re:Am I the only one getting sick of this? (Score:5, Interesting)
Flying cars don't need flying drivers, they need driving pilots. There are about 650,000 pilots in the United States with a certificate of Private Pilot or better. (the minimum license necessary to take more than 1 passenger in a flying vehicle) Compared to the population of 300 MILLION people, and you find that there are an awful few people who could "drive" a flying car. You find the economics of scale that will work at this level. Certainly, Detroit won't. Flying isn't the same as driving. There are no roads, and you have to pay careful attention to long-established procedures designed to avoid situations like running out of gas. (a minor inconvenience in a car, potentially fatal in a plane if you aren't well trained to handle it) I hate to diss flying, since I'm a pilot by hobby, and I love my hobby. But the requirements to pilot are significantly greater than the requirements to drive.
Nuclear Fusion is widely available. Look up. (you have to go outside to see it - it's called the "sun") As a source for electricity, it's coming at prices comparable to coal [slashdot.org] which is the cheapest non-renewable form of energy today in the USA.
Data storages has generally followed Moore's law, with a doubling time of about 18 months. What more do you want? I remember when a 100 MB HDD was big. Now, a little over 2 decades later, I routinely transfer files bigger than that all around the world via the Internet, and save to a flash disk the size of my thumb that requires no external power source, while my LAPTOP hard disk is 2,500 MB in size. I won't highlight my workstation/home-server with > 3 TB of storage.
Amazing!
Try using a 10 year old computer sometime. You'll be amazed at just how far we've really come.
And, technology is advancing on ALL fronts.
I recently added on to my home, doubling its size. Along with that came new regulations for insulation, higher-efficiency heating/cooling unit, insulation, double-paned windows, etc. I DOUBLED the size of my home, but my heating/cooling bill is about HALF what it used to be. Progress? Suffice it to say that the money I'm saving on my utility bill easily beats the monthly cost of the financed retrofit upgrades to my original home! In other words: it would be cheaper to buy the upgrades to an existing 100 year old home to get these improvements than to keep using whatever you had in the first place.
I drive a 10 year-old Saturn. It gets 30 MPG fully loaded at 90 MPH, quietly, with air conditioning, decent radio, and air bags. Back in the 1980s, I drove a VW diesel Rabbit that did about the same at the same speed. It was noisy, shook lots, had an AM-only radio, and didn't have A/C. Relative prices (inflation adjusted) makes the Saturn CHEAPER than the VW Rabbit. Hello progress ?!?
I use CFL lights throughout my home. Over their lifetimes, they are cheaper than incandescents in replacement costs alone, and 5 of these things use less electricity than a SINGLE incandescent bulb. I can light up my whole house for what it used to cost to turn on the porch light. I've banished incandescents from my home. And, I'm still not particularly good at turning
Re:Supersonic Tesla (Score:3, Interesting)
Re:Dupe (Score:5, Interesting)
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'.
Interview with Dr. Cui (Score:3, Interesting)
Re:Good deal (Score:3, Interesting)
The energy input required to make solar panels is one of the major concerns in the design process, particularly for anyone proposing cheap methods.
Cheap, long lasting battery systems plus low cost, efficient photovoltaics would allow a large amount of residential electricity use to be met by solar. Just panel every south facing roof. At the moment the cost is high, but the intrinsic cost of manufacture is rather less.
Re:Am I the only one getting sick of this? (Score:3, Interesting)
1. I would never have believed when I was at university exactly ten years ago, that in 2008, I would have a more powerful processor in my *telephone* than I had in my desktop computer I took to uni to study Computer Science with.
2. I would never have believed ten years ago that I could get 4 GIGABYTES of non-volatile memory in something the same size as my little fingernail (MicroSD) for a few pounds off eBay.
3. I also bet my colleague about 3 years ago that you would NOT be able to ever run your computer from any kind of solid state hard disk until at least 2010. I lost the bet - I assumed the OS and data would get bigger faster than solid state storage would increase in size, but 64GB SSD drives are now affordable and would easily take all my files on any of my computers.
4. We can access the Internet in the lounge, park or coffee shop at multi-megabit speeds, often for free. 10 years ago MOST people had never even heard of "broadband" and I was paying £20 per month for Demon DIAL UP at 28.8K. If you'd said that someone could get 2-8Mbit internet over shitty copper phone lines from a mile away, they'd have laughed. At the time I was struggling to make a 10Mbit work just within the confines of our office. Now our office as a 20MBit internet connection just a few years later. When I graduated from Uni in '99 (CompSci) our entire halls of residence (over 100 people) was connected back to the uni with one 64Kbit leased line - which cost the uni nearly £2000 per month. Now they have 100Mb broadband in every room connected to the uni using a laser.
I doubt MOST people would have believed any of these things would be possible in only 8-10 years - even on slashdot but sometimes it just does happen.
On the other hand there are some other surprises. If you expand the old graphs of PC processor clock speeds, we should have 12GHz CPUs now, but we don't. Clock speeds stopped increasing about 4 years ago. Processors are still faster due to architectural changes, faster bus speeds and more cores, but clock speeds are exactly the same if not slower than they were a few years back. My 4 year old desktop has a FASTER clock speed (2.4GHz P4) than my brand new more expensive desktop (2.2Ghz Core 2 Duo).
Re:Dupe (Score:1, Interesting)
Re:Dupe (Score:4, Interesting)
Re:Dupe (Score:3, Interesting)
What is the total weight of the car batteries? How much energy will be spent physically swapping them? This isn't just a starter battery... If nothing else, this would probably be the end of the self-service gas station (at least until our car-refueling robot overlords sweep in to save the day)... And remember, it's the driver that's going to end up paying for any labor, or any energy expense in general from swapping batteries.
Another poster's concern about some batteries being in better condition than others doesn't seem like a huge deal in and of itself. The battery station is going to have to monitor the condition of the batteries in its inventory to dispose of them when they're no longer usable; so there's going to be some standard minimum: "you will get at least X out of this battery swap." Maybe you get more sometimes -- nice bonus. The station might set tiered pricing -- for an extra $x.xx you get a better guarantee about the condition of your new battery...
However, unless the station can penalize you for degradation of the battery you turn in (relative to the condition in which you got it), there will be no incentive not to mistreat batteries. What exactly that means will depend on the battery technology, but generally some usage patterns are better for overall battery life than others. If the average battery is abused, average overall life goes down, and then cradle-to-grave energy efficiency goes down (as you have to manufacture / recycle more batteries).
There would be overhead on the station's end to keep a sufficient inventory of charged batteries. To keep that to a minimum, there should be pretty tight standards to make all cars' batteries interchangeable. Is that currently the case in electric cars? How practical is it to have one (or at least a small number of) standard battery? (Again, we're no longer talking about the market for starter batteries here...)
Suppose I swap out my batteries and the replacements fail catestrophically; who all has liability exposure? The station? The previous owner? The manufacturer? How do you keep track of a battery's lineage of ownership?
Ooh, crazy Bad Hollywood Plot theory time -- a terrorist quietly assumes control of a battery station. Over the course of a few days, he swaps out the batteries from as many cars as possible, replacing them with packages that are half battery, half explosive. Once his devices are distributed, across the city vehicles start exploding at random. Film at 11.
The Slashdot summary and news.com are incorrect (Score:2, Interesting)
In terms of cycles, they have data in their supporting info document that shows they have only tested a cell with this electrode up to 30 cycles! So no discussion of battery life can even be made.
Energy density can be found by knowing the capacity of each electrode, the electrolyte properties and volume, and the cell voltage (which is usually about 4 V for Li-ion batteries). They claim to have reached their theoretical maximum 4200 mAh/g capacity for a Si electrode. This is indeed ~10x the capacity of graphite anodes, which are the lowest capacity anodes used in Li-ion batteries (300-400 mAh/g). More common carbon (C6) anodes are about twice that. And, in fact, Li metal anodes have about the same capacity, 3800 to 4000 mAh/g, as these Si nanowires. So the capacity is hardly a breakthrough. However, they may be more safe than Li metal: "Li metal" batteries are Li-ion batteries with Li metal electrodes, which have had safety issues due to Li dendrites (trees) growing between electrodes and shorting out the cell. This article [nature.com] (needs subscription) from years back explains the details of electrode choices and other challenges regarding Li-ion and Li metal batteries. It seems these Si nanowire electrodes may yield similar energy density to Li metal, or several times that of the Li-ion batteries that are in common use.