New Lithium-Air Battery Delivers 10 Times the Energy Density 281
Al writes "A company called PolyPlus has developed lithium metal-air batteries that have 10 times the energy density of regular lithium-ion batteries. The anode is made up entirely of lithium metal, and the surrounding air acts as the cathode, making the batteries incredibly energy dense. Previous efforts to make lithium metal batteries have been stymied by the sensitivity of lithium to water in the air. The new batteries use a sophisticated membrane to protect the lithium anode and PolyPlus has even created a version that works underwater, by drawing oxygen through the membrane. Lithium metal-air batteries could be light-weight power sources for demand for plug-in hybrid vehicles and consumer electronics; IBM also recently announced that it would develop lithium metal-air batteries for the energy grid and for transportation."
Re:Explosions (Score:1, Informative)
I'm no battery scientist, but I wonder if these batteries will be more or less safe compared to the lithium-ion batteries
if the energy density is higher, that normally means "less safe".
interesting, nearly-relevant article [dansdata.com]
Re:Explosions (Score:3, Informative)
(From the TFA)
The safety concern is the main problem here.
Deja Vu (Score:3, Informative)
Completely unlike the Lithium Air battery on /. a month ago: http://hardware.slashdot.org/article.pl?sid=09/05/21/1237231 [slashdot.org]
Re:Explosions (Score:3, Informative)
Re:Explosions (Score:5, Informative)
Or if you even looked at the article, you would see a demo of it running underwater.
Re:Double edged sword (Score:5, Informative)
No, it isn't.
Lithium-Ion batteries are dangerous because of very low internal resistance. ie. They can dump a large amount of current in a very short time. This is completely independent of energy density, and future designs could well have higher energy density with less danger of thermal runaway.
Re:Explosions (Score:5, Informative)
Diesel fuel has a very high energy density and very little explosive potential. The danger comes not from the contained energy, but how fast that energy can be released.
Re:Rechargeables in "early development" (Score:3, Informative)
The article uses the term "Single Use"
Actually, 1800's batteries were Better! (Score:4, Informative)
Actually, from the very edge of the 1800's. Development didn't complete until 1901.
http://en.wikipedia.org/wiki/Nickel-iron_battery [wikipedia.org]
Nickel-Iron (NiFe) batteries don't appreciably degrade from discharge. There is some wear, but they can last for 50 years if you change the electrolyte. Power and current densities are low, but they are ideal for photovoltaic installations. Battery wear from deep discharge is one of the biggest economic factors of solar power cost.
You can buy them, but currently only from manufacturers in India and China.
Re:Same old story... (Score:4, Informative)
It's a word used in chemistry, surface science and materials engineering. In that context, it means "add a functional group." http://en.wiktionary.org/wiki/functionalize [wiktionary.org]
Re:Same old story... (Score:3, Informative)
Funny is a good mod rating for that. It's always funny when someone makes fun of someone for their use of words without taking the time to look up what the words actually mean. Do a google search for "functionalize" and "carbon". You'll find 563,000 hits. Most of the prominent ones are peer-reviewed scientific papers. Functionalization, in a chemistry context, means to add a functional group [wikipedia.org] to a compound.
Energy Density Fears (Score:5, Informative)
A lot of people are raising concerns about the risk associated with increasing the energy density of the battery.
I would like to point out that it's difficult to directly compare the risks of two fuel sources without knowing how quickly the energy can be released, and under what conditions it can happen.
For instance, I enjoy working with motorcycles, which typically carry 2 major energy sources: A battery, which supplies starting and auxiliary power, and gasoline, which supplies primary power (including the power required to charge the battery.)
The gasoline in the tank has a far greater energy density and far higher energy potential than the battery, but of the two, the battery poses the greatest risk of injury and explosion.
The gasoline can certainly burn, but will only explode under very specific conditions. The conditions required to set it burning are also very easily removed. In fact, I'm far more concerned about the chemical damaged caused by exposing fuel to skin than I am about the risk of fire or explosion.
On the other hand, I work around the battery with wrenches that are typically grounded against the frame while in use. Even with a disconnected battery, I've had cases (while working on a car) where the wrench contacts the positive terminal of the disconnected battery, creating very heavy gauge short circuit between the terminals. The resulting release of energy will cut through metal and cause severe burns. Likewise, if overdrawn, the battery can release hydrogen which can either vent and ignite, or build internal pressure causing the battery to explode.
An interesting example of a substance that is explosive, has a high energy density, and is safe is C4, which can actually be used to cook food if burned, but will not explode without a blasting cap.
So... Are these batteries a risk? Perhaps. We should look into that. But it's best not to cry about the sky falling without first investigating the matter.
Re:Lithium, a limited natural resource? (Score:5, Informative)
"Like many other producers of crude oil, Bolivia finds itself in a frustrating situation regarding its processing and the refining of its raw materials. It finds company in the history of the incumbent automobile fuel source, petroleum. There is a great deal that the Bolivians could learn from the Saudis regarding what they should do with its lithium reserves and how to extract them. To achieve this, Bolivia will want to strive to find the answer to a number of questions with which the Saudis have dealt over the years, and continues to deal with, such as how wealth will be distributed if the commodity is nationalized, how to maintain a balance between maximum production and environmental stability, and what will stabilize the economy once the commodity is exhausted."
http://www.coha.org/2009/02/lucky-bolivia-and-the-future-of-lithium-in-the-world-economy/
Re:Explosions (Score:2, Informative)
Generally, if it stores energy, there usually is a failure mode which involves the rapid release of the stored energy in an unpleasant manner.
Important part: "a failure mode." Triggering via blasting cap is TNT's "failure mode." If you put aluminum in a dust form and then aerosol it, it'll be much worse; that's aluminum's "failure mode." Heck, flour has a similar failure mode and as such has blown up several bakeries.
Re:YEAH RIGHT (Score:4, Informative)
The only people who make this argument are those who haven't paid attention to battery energy density over time. If you don't know what I'm talking about, compare your cell phone with one from the early 90s, or your laptop battery. Battery energy density has increased 4.5x in the past 20 years, and power density 10x. And it only seems to be speeding up.
Yes, there was a long time (the first 2/3rds to 3/4s of this century) where battery technology was mostly stagnated. Then the consumer electronics industry came into its own, and people actually started putting serious money into battery research. And our modern understanding of chemistry and nanoscale structures certainly doesn't hurt.
Or a halogen flashlight could SHINE for that long. But no, they're always still the same sucky thing as in the 1800s
Um, do you realize where the term "flashlight" comes from? Flashlights in the 1800s (actually, the very end of the 1800s) were these big, massive things with huge, heavy batteries -- and despite this, they had so little energy density that you couldn't leave them on all the time. You had to "flash" them when you wanted to see something.
Re:Explosions (Score:2, Informative)
Re:I'm so happy 'cause today I found my friends (Score:5, Informative)
However, the big catch is that we can't really produce enough Lithium to make all those batteries.
God, that myth just won't die [gas2.org], will it?
But there's probably no practical way to extract it.
Of course there is. There are dozens of ways. Here's one [osti.gov] -- $22-$32/kg. Given that 1kWh of automotive li-ion batteries takes 1-2kg of lithium carbonate and costs about $500, that's a pretty minor cost. More expensive than the surface-mined stuff, mind you (which runs $5-8/kg), but eminently affordable.
Re:Same old story... (Score:3, Informative)
False again!
First off, "li-cell" != "li-ion". A "li-cell" is a "lithium battery", which is a type of primary cell, and which predates lithium-ion to the market. Secondly, you're absolutely wrong in your assertion. Even traditional cobalt cathodes alone have gone from ~1200mAh in 1994 to almost 3000mAh in 2008 [batteriesdigest.com]. In the past year and a half alone, li-ion batteries on the market have gone from 160Wh/kg to 200Wh/kg. For God's sake, research a topic before you start spouting off about it.
Have you seriously not noticed how battery life keeps going up at the same time the batteries keep getting smaller? And if so, how did you get net access to make that post from your cave?
Re:Same old story... (Score:3, Informative)
There are 9v rechargables:
http://thomasdistributing.com/shop/ipower-9-volt-500mah-lithium-polymer-rechargeable-batteriesbr9v-lithium-rechargeablebrone-9v-rechargeable-battery-p-548.html?SP_id=&osCsid=iu4reqeohaenijtqokk2mgo5j6 [thomasdistributing.com]
Or if you want NIMH:
http://thomasdistributing.com/shop/maha-9v-300-mah-nimh-rechargeable-battery-p-503.html?SP_id=&osCsid=iu4reqeohaenijtqokk2mgo5j6 [thomasdistributing.com]
I've switched out all of my AAA and AA devices in the house to low discharge NIMH batteries. The only thing I can't use my rechargables in is my thermostat - the voltage drop is just a little too much for the LCD panel on the front. I'd have to think you'd save money in the long run using rechargables in the foot pedals - and you could still keep a few alkalines on hand if you run out of juice.
Re:Explosions (Score:5, Informative)
If you put aluminum in a dust form and then aerosol it, it'll be much worse;
Irrelevant. That *block of aluminum* has more energy density than TNT. *So does aerosolized aluminum*, but so does the block. And it has more energy than gasoline per kilogram, too.
Just because something has high energy density does *not* mean it has a realistic way to release that energy rapidly. And the amount of energy contained within the chemicals that make up a battery (releasable by burning) are often way more than the amount of electrical energy stored in the battery, so saying that because the electricity stored went up 10fold means somehow that the chemical energy that would be released in a fire went up 10fold is just wrong.
If I added a resistor to the inside of a battery so as to waste most of the power of the battery, causing the energy density of the cell to decrease tenfold, would it somehow suddenly become ten times less flammable? If I took the resistor away, would it suddenly become ten times more flammable? Don't act like that's far-fetched, because that's very similar to how a lot of battery improvements work -- lowering the internal resistance, making sure that more of the material within can take part in the desired electricity-storage reactions, and so forth.
There are some incredibly flammable low-energy density batteries, and incredibly fire-resistant high energy density batteries out there. Heck, the Zebra battery has almost the energy density of the lower-end li-ions, and it operates at temperatures of hundreds of degrees in *typical usage*. The amount of electricity stored is simply not inherently correlated with the energy density.
Re:Free and "Fun" Experiment (Score:5, Informative)
I was warned that car batteries can explode if you short-circuit them in this way.
All batteries have internal resistance which naturally limits the amount of current, and therefore power, they can put out. They are unlikely to "explode" in the same way a firecracker explodes... at least from the chemistry alone.
What can happen, though, is the high power draw form shorting a battery will cause a LOT of heat generation. The stuff inside the battery expands with this heat, maybe even vaporizes, and if the battery casing is relatively inflexible it could burst. Bursting is not *quite* the same as exploding.
BUT! Lithium is nasty stuff. If a lithium battery bursts, exposing the lithium directly to the air, then you might get some real pyrotechnics going.
=Smidge=
I know you meant this as a joke, but.... (Score:3, Informative)
In the recent case of United States v. Irizarry, a man in New York was arrested and charged with a felony weapons violation (under the switchblade laws) for having a Home Depot "Husky" brand folding utility knife clipped to his pocket.
In related news, the Department of Homeland Security has just issued a new ruling defining all knives that can be opened with one hand by way of thumbstud, ridge or hole -- which means most pocket knives made in the past 20 years -- as "switchblades" whether they have a spring or not. The huntin' and fishin' crowd are pretty much up in arms over that fact that most of them just became criminals. If you carry a recent Leatherman, you're committing a felony under the new rules.
And finally, a man last year was arrested for trying to enter a federal building with an old one-inch army surplus can opener attached to his keychain.
You meant your post as a joke and a satire, but it's already reality.
Re:Free and "Fun" Experiment (Score:3, Informative)
Unless you are referring to cars fueled by propane, you have been watching too many movies. Neither gasoline nor diesel fuel are explosive in their liquid state.