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Degraded Electrodes Observed In Aging Batteries
schliz writes "Scientists have identified nanoscale changes in aging lithium-ion batteries that could be responsible for their degradation over time. By dissecting and examining dead batteries, they found that some lithium was irreversibly lost from the positive to negative electrode of dead batteries, and no longer participated in charging and discharging. They discovered that finely-structured nanomaterials on dead batteries' electrodes had coarsened in size, and theorise that the coarsening of the cathode may be responsible for the loss of lithium."
I thought that's the way they were engineered - to generate revenue by way of having to replace them annually.
Gimme a break. These batteries are based on electro-chemistry. You know, interactions between molecules. Everything that goes on in batteries, all batteries, are nanoscale, by definition. Corrosion in the electrodes had been known and studied for ages. It is a damn chemical reaction that will happen at molecular level.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
"Things degrade and break over time, especially if you use them."
How this is news ? WTF?
And instead of just taking the "attributed" reason they bothered to do some work and report on what they suspect is the actual physical/chemical cause rather than just a catch-all "disorder". Since that helps with trying to reduce the problem.
Why didn't you do that sometime in the last 20 years if it was so damn obvious?
A small solar cell isn't going to do shit, and whenever you're not using it, it's just a waste. Leaving batteries in the sun is a recipe for failure, so leaving battery-powered devices in the sun is the same. (Most of those solar battery chargers are fucking lame just for this reason, including ALL candybar chargers.)
If you want a small solar charger, carry it separately. You can get one with LiIon batteries in it from SlaveryExtreme for about $13.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I'm glad you put the "[NB - sarcasm]" bin in there. I was just about to hopelessly embarrass myself by taking that seriously [NB - sarcasm].
Why OpalCalc is the best Windows calc
I woudn't google SlaveryExtreme if I were you.
Because 90% of electronics can't run anything off the power supplied from a solar cell. Solar stuff is still inside the calculator / overnight trickle charger range of power.
Hell, it can take 8-10 hours to charge some AA's in some (not entirely dark) countries. If I have one as big as a folded out suitcase, I might *JUST* be able to get enough juice to start my car once if I leave it in direct sunlight for a few hours / days.
Seriously, your average laptop can pull 90W during booting (19V 4.5A isn't unusual on a PSU). To get even 10% of that, you need a good solar cell of a good size - a folded out briefcase sized solar panel gets you about 13W max (and that only at 12V so it would need to be converted up) with a standard product I can buy today - running in good light. On that briefcase I mentioned it says "During peak hours of sunshine, a mobile phone can be charged in an hour.". It weigh 4.5 kg.
You could SMOTHER your 19" screen laptop in solar cells (back and front and inside and out), add several kilos to the weight, leave it with direct sunlight from all directions, and STILL it would be hard pushed to do more than trickle-charge your battery or run an incredibly low power computing device. A single USB port sucks 5V at 500mA = 2.5W. Four USB ports and you're hitting the maximum of that briefcase which has a similar surface area, under theoretically ideal conditions.
Solar is a complete WASTE at the moment because it's nowhere near efficient enough, in terms of energy density, small scale deployments, etc. It can just about so what people now use it for: calculators, a very, very slow trickle charger, a couple of solar lights (almost always LED's so they are as low power as possible) running for a few hours at night after a day of sunshine. When it hits reasonable amounts of power, then you can begin to even think about anything like that.
If you want to get an idea of things like this, buy yourself one of those cheap wind-up / solar / battery torches that you can find cheap. Spend a week using the torch all day / listening to the radio from a 99p set of batteries. Then spend a week doing the same via solar. Then spend a week doing the same by only hand-cranking. The battery will last for possibly months. The solar cell will probably give you a good few hours - if you're lucky in your weather it'll be able to do 24/7 on such a low-power circuit. Hand-cranking will have you worn out by lunchtime. I guarantee you you will find a new respect for the amount of energy in the average set of batteries and the current efficiencies of things like solar cells and cheap electronics.
To summarise: Solar is shit. Most renewable energies are shit. But we're trying to make them better because we've been so spoiled in the last hundred years by simple things like zinc-carbon batteries, let alone anything more modern.
But there are those for whom it was absolutely needed.
Oh, I'm sorry, discovering WHY and HOW things happen suddenly isn't science. The only thing that's science is doing "real work". Strangely, I used to call that engineering.
I woudn't google SlaveryExtreme if I were you.
If people don't know what DealExtreme is, or if people don't know that all this $2.99 shit coming out of China is built with slave labor, or can't put these two facts together, then they probably don't need to be buying any cheap chinese shit anyway.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
It was supposed to be a kind of joke, because I made the same 'error' you did ;)
Why OpalCalc is the best Windows calc
You forgot the cost of electricity for charging!
Cantankerous old coot since 1957.
Communication is a muddled action.
Sticking solar panels on things you put in your bag/pocket is dumb, but solar does work well. You can pretty easily carry 50W+ of solar cells, which is enough to run most any laptop (you still need a charging circuit and a small battery as a buffer). http://www.katerno.com/detail.php?s=92637
One place where solar panels should be, and aren't, is on hybrid cars. As far as I can tell, they aren't included mainly because of laws mandating that cars meet gas-type requirements(i.e. the US version of the Prius still ships with the EV Mode button torn out). You can get a Prius with solar panels, but they are ONLY used to power ventilation and never charge the batteries for the motor.
You should probably be quiet. If you think solar power is good for overnight trickle charging, you don't understand the technology.
This is some just really old news. Papers have been published on this and the other myriad sources of lithium battery degradation over the last several decades. In fact, this sort of coarsening, irreversibility, and poisoning are common in all such "nano" and even "micro" systems in which thermodynamics and kinetics are pitted against each other. For instance, at a three day international workshop on automotive lithium batteries half a decade ago, about a third of the talks were on various degradation mechanisms in these systems. On the other hand, this might be something completely knew that no one in the materials science or electrochemistry fields have heard of, but, being one of those people, and seeing the utter lack of detail in the news article and not being able to find the originating scientific publication, I doubt it. It looks like one of many articles on the subject that someone happened to pick up and submit. And yes, I'm a materials scientist and I study nano-scale materials, including battery electrodes.
I'm not looking foward for the time the Sun turns into a red giant... Now, solar isn't shit. It is just not suitable to be used as a portable power source.
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What are the implications for EVs, which seem to primarily use Li based batteries?
I know the 'record' for these batteries is pretty good so far (not bad enough to make Consumer Reports respond yet, at least), but I have to wonder how much of that is due to ideal environmental factors and how much of it is due to the things not being out long enough, or used enough, to get an accurate measure. How are the first generations of the Prius doing? I've yet to see any reviews or analysis. This is important for the used car market (to assure there is one in 10 years, and automobiles don't become disposable due to the cost of replacement).
A $20-30k vehicle lasting a mere 5 years before needing primary propulsion to be replaced is pretty crazy, especially when it involves a non-trivial amount of Lithium to do so (not exactly the most common of alkali metals).
I'm sure there's probably a technological way to prevent or slow this from happening, but for the time being, we're stuck with the technology we've got. Combine this with the lifecycle degradation of cold and heat on Lithium cells, and they seem to be a really poor broad-application general-purpose power sequestering method.
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
It has pretty decent implications for vehicles. Even with a lead-acid battery, a small amp positive trickle charge will go a long way to making your battery last longer before it's in need of replacement.
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
People usually have many opinions on how you should use laptop or phone batteries to maintain maximum longevity. Keep it plugged in always when possible, discharge it to 50% every now and then, or always run it from full to empty, etc.
It would be cool if we had some "battery mythbusters" who would systematically test these things with different machines and usage patterns so we could get more solid data on the subject. :)
You get a core deposite back that reduces the cost of the new battery. If you don't return your battery when you buy a new one, the new battery costs approx. $20 more.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
This is where we need supercap technology to actually get working and usable for small devices. This way, we can replace the batteries in hard to access devices with supercaps that don't depend on a chemical reaction to store charge, and can be charged/discharged millions more times than a battery.
+1 funny
Funniest comment I've seen so far today!
*sigh* back to work...
It has pretty decent implications for vehicles. Even with a lead-acid battery, a small amp positive trickle charge will go a long way to making your battery last longer before it's in need of replacement.
Yeah, I have a Coleman solar charger that plugs into the cigarette lighter in the dash. It's about 10cm wide and 40-50cm long.
During the winter months when I don't go anywhere for a week or two at a time, it's the difference between a dead battery and one that will still start the car after two weeks. (If I don't *have* to go out on snowy/icy roads, I won't. And generally, I don't need to unless something comes up. I don't go stir crazy unless the internet stops working.)
Handy little thing. Excellent for any vehicle that you don't drive at least weekly. I just wish it was wired permanently into the system and mounted somewhere.
Wolde you bothe eate your cake, and have your cake?
News flash! Old stuff wears out and doesn't work as well!
Next up: A study on why my 20-year-old car isn't working like its brand new anymore.
No, there is no "-1 I'LL NEVER ADMIT BEING WRONG!!!" mod.
Very true, and an important concern. However, the average lifespan of a cap is definitely longer than a battery, especially if coupled with charging circuitry that can tell the dielectric is about to arc across and not keep stuffing farads in the thing.
The problem is that caps don't have enough energy/weight to make them a battery replacement yet.
oh yeah, I'm really so stupid that I'd be posting from her account.
Obviously this is my girlfriend's account.
Too bad it's too late for moderation, that deserves a +5 funny!
Free Martian Whores!
And to be greater than 10 times lower in energy density than lead acid batteries.
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It gets attributed to Entropy.
No. You have no clue what entropy is. Entropy is a state function of the molecules. As the battery is charged and discharged, it changes. Look at your molar entropy tables.
Second, it is known not to impact some batteries. Edison cells are still producing %100 of their rated capacity after almost 100 years of operation. Iron plates = no shape change.
"This just in - scientists use vacuum tunnel and state of the art electronics to detect that gravity accelerates two different masses - at the same rate!!" [NB - sarcasm]
It would be news if they found, down to say 10^-15, that both masses are accelerated the same.
Responsibility is an addiction
Virtue is a temptation
Community is a cartel