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Power Technology

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."
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New Lithium-Air Battery Delivers 10 Times the Energy Density

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  • Same old story... (Score:5, Insightful)

    by abigsmurf ( 919188 ) on Friday June 26, 2009 @03:41PM (#28487053)

    "it expects these batteries to be on the market within a few years"

    Just like those ultra efficient, cheap, solar panels we've been promised 'next year' each year for the last decade.

    • Re: (Score:2, Interesting)

      by Hadlock ( 143607 )

      Exactly. Call me when I can buy AA sized versions of these at WalMart. Or upgrade my Powerbook(Macbook Pro?)'s batteries using this commercially. The budding musician in me wants a long lasting 9v battery that costs less than $4.

    • Solar panel efficiency is progressing slowly but steadily. Evolution instead of revolution. Todays panels are way better than panels made a few years ago.

      Todays panels aren't ultra efficient, but they get the job done. Price isn't an issue anymore, the break even point is just a few years.
      • Re: (Score:3, Insightful)

        by GooberToo ( 74388 )

        Price isn't an issue anymore, the break even point is just a few years.

        Not according to the article on Slashdot just a few days ago. You'll looking at break even in 14-20 years for any entire system which can take your house off the grid. And that assumes a very sunny location.

    • Re:Same old story... (Score:5, Interesting)

      by Rei ( 128717 ) on Friday June 26, 2009 @03:52PM (#28487251) Homepage

      Your pessimism is misplaced. Don't you remember cell phones from the early 90s? Those giant bricks? When the then top-of-the-line NiMH battery was introduced in 1989, it boasted 45Wh/kg energy density. Now we have li-ions widely available at 200Wh/kg (4.5x the energy density) and 10x the power density.

      For any given tech advance, the odds of it making it to market are low. But there are so many tech advances, many of which you never hear about, that the tech continues to advance at a good clip.

      That said, I'm not a really big fan of any X-air batteries. They tend to be inefficient, low power, expensive, and have poor cycle life. There are literally dozens of li-ion advances working toward commercialization that can each 1.5 to 8x the density of either the anode or cathode, so regular li-ion still looks to have a lot of life in it. Also, I'm particularly interested in the recent advancements in lithium-sulfur. Practical lithium sulfur cells are 3-4x the energy density of current li-ion and are efficient and with reasonable power (excepting the unimpressive "stabilized" ones), but they tend to have very short cycle lifes. The University of Waterloo came up with a really interesting approach of wicking the sulfur into the pores of mesoporous carbon, baking it off the outside, and then functionalizing the carbon surface with PEG to repel the hydrophobic sulfur and keep it trapped in the pores so it can't migrate across the membrane and precipitate useless lithium polysulfates (the normal means of capacity loss in LiS). Their results were pretty astounding. In one experiment, they deliberately used an electrolyte known for dissolving polysulfates, thus facilitating capacity loss -- and compared their electrode with a traditional one. In a couple dozen cycles, the traditional electrode lost something like 96% of its capacity. Theirs lost only about a quarter of its capacity.

  • I suspect primary.


    • So do I.

      The technology sounds very similar to the aluminum-air batteries that have been around for years, though not commonly used. They work by oxidizing the aluminum, and the process is not reversible (at least not within the cell.)

      You "recharge" aluminum-air batteries by dumping out all the aluminum oxide (which maybe can be recycled back into aluminum in a smelter), and installing fresh aluminum plates.

      I wouldn't want to try that trick with plates of pure lithium...

    • by Rei ( 128717 )

      Incorrect. The lithium oxidizes to lithium peroxide, which can be reversibly transformed to lithium metal and free oxygen.

  • Energy density is a double edged sword. Yes, I would love to have ten times the runtime of my laptop. But there are inherent dangers. The current Lithium-Ion batteries are pretty dangerous when they are mistreated. Having ten times the energy stored in a battery? I'm not sure that is a blessing or a curse. Burning down your house isn't worth having a longer lasting laptop;
    • Re: (Score:3, Insightful)

      by trybywrench ( 584843 )
      I'm not sure that is a blessing or a curse. Burning down your house isn't worth having a longer lasting laptop;

      I know what you mean but you could also say burning down your house isn't worth having a stove. You just need to know that the battery can be dangerous and you should handle it accordingly.
    • by evilviper ( 135110 ) on Friday June 26, 2009 @03:54PM (#28487287) Journal

      Energy density is a double edged sword.

      No, it isn't.

      But there are inherent dangers. The current Lithium-Ion batteries are pretty dangerous when they are mistreated.

      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.

      • 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.

        Nope, that's not it either. Low internal resistance is a good thing, well correlated to power (not energy) density. Lithium ion batteries are mostly dangerous because they're flammable; short them out or overcharge them and they'll catch fire. If they merely got hot they'd be a lot less dangerous.

    • Use the increased energy density to get super light batteries with the same total energy content and hopefully safety. Sounds like a win to me.

    • by LordKaT ( 619540 ) on Friday June 26, 2009 @04:00PM (#28487409) Homepage Journal

      My laptop constantly overheats, I mistreak the battery to hell, and still it keeps working.

      And millions upon millions of other people have had the same results.

      I've only got one piece of advice for you: stop being such a pussy. You're slowing the rest of us down.

    • Re: (Score:2, Insightful)

      by rally2xs ( 1093023 )
      Batteries may be somewhat dangerous, but right now we're parking our cars in our garages with 15 gallons of gasoline in the tanks. If it gets out, it flows all over the place. It also fills the air with an explosive gas that will also cause poisoning in people, or at least intoxication. Lose one threat, gain another. The battery is probably safer than the gasoline.
    • Re: (Score:2, Interesting)

      by need4mospd ( 1146215 )

      If you think about it, single edged swords are also double edged swords. I mean, it cuts on one side, but not the other....

      I think I just blew my own mind.

    • Burning down some idiot's house who mistreats his laptop is totally worth you and me getting longer-lasting laptops, though. If they can be made safe enough for people who don't abuse them, they're safe enough. I haul gasoline in a big tank in my car right now, for example. There's some danger, but I've never been burned or blasted by it yet.

  • Deja Vu (Score:3, Informative)

    by evilviper ( 135110 ) on Friday June 26, 2009 @03:48PM (#28487169) Journal

    Completely unlike the Lithium Air battery on /. a month ago: http://hardware.slashdot.org/article.pl?sid=09/05/21/1237231 [slashdot.org]

  • by dtolman ( 688781 ) <dtolman@yahoo.com> on Friday June 26, 2009 @03:49PM (#28487199) Homepage
    There's no here here. They don't have any real batteries in production. Its still in real-world testing. Or to put it in more slashdot-centric way of thinking... they don't even have 2/4 steps for profit 1) Announce untested idea for new battery 2) ?????? 3) ?????? 4) Profit!
  • Batteries suck. There have been many times when batteries would be "10 times" more better than some previous generation. But they never are. Batteries would only be good if cellular phone could run at least a MONTH on them. Or a halogen flashlight could SHINE for that long. But no, they're always still the same sucky thing as in the 1800s, and not the 10 times more powerful than should be if all the times someone claimed they were "10 times better" would be true.
    • In the parent post, I meant 10^3, but slashdot ate away the ^3 symbol. Also, I mean, do you know what 10 times more means? It means a laptop that now works 3 days, should work 30 days. Do you believe that? I don't. Even though with our technology I find that we should be able to. And that is why I'm frustrated about batteries.
      • I meant 10^3, but slashdot ate away the ^3 symbol.

        A whole new category of homework and test related excuses is discovered!

      • Even though with our technology I find that we should be able to. And that is why I'm frustrated about batteries.

        Oh, we can. But as my electrochem professor put it, as you move towards better energy density you also move towards making what is essentially a bomb. And I don't think you'll be able to get that 30-hour laptop battery on an airplane...

    • by StCredZero ( 169093 ) on Friday June 26, 2009 @04:07PM (#28487501)

      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:YEAH RIGHT (Score:4, Informative)

      by Rei ( 128717 ) on Friday June 26, 2009 @04:52PM (#28488099) Homepage

      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.

  • by michael_cain ( 66650 ) on Friday June 26, 2009 @03:54PM (#28487293) Journal
    Both articles pointed to by the original post note that rechargeable lithium-air batteries are in "early development". It may be worth noting that zinc-air batteries (fuel cells, more accurately, as these lithium devices are currently) have been available for some years now. The problem is the recharging step, ie, making it a battery instead of a fuel cell. Splitting zinc oxide to get relatively pure zinc back, all within the original container, remains an unsolved problem, in practice. These lithium devices will face the same problem: how do you use electricity to efficiently split lithium oxides to get lithium and oxygen again? If they have indeed solved that problem, and can apply it to other metals, zinc may be a better solution overall, even with somewhat lower energy density. The global mineral reserves are much larger and the problem with water goes away.
  • A few years for this product on the market is too long, I know through reading through some patents that they are currently working on different types of polymer batteries which are actually lighter than lithium polymer batteries. If one of these polymers hits the market before or at the same time as these batteries then it will be no competition on which will dominate the market. If they want to make money they need to get these on the market faster than a few years.
  • If these batteries really can store 10 times the energy of current batteries, they could be revolutionary. They could make the electric car more practical than using gasoline.

    However, the big catch is that we can't really produce enough Lithium [wikipedia.org] to make all those batteries. There is a plentiful supply in the water: "Seawater contains an estimated 230 billion tons of lithium, though at a low concentration of 0.1 to 0.2 ppm." But there's probably no practical way to extract it.

  • by mwilliamson ( 672411 ) on Friday June 26, 2009 @04:04PM (#28487465) Homepage Journal
    It seems like this is the holy grail for electric vehicles, and we can finally stop burning dinosaur juice in our little bitty engines and realize the economies of scale of burning dinosaur farts in really big and efficient prime movers. This is all well and good, but how plentiful is lithium, and can it be recycled easily (I suspect yes)? -Michael
    • by trybywrench ( 584843 ) on Friday June 26, 2009 @04:32PM (#28487851)
      It's Bolivia that has all the Lithium. They are already freaking out about corporations raping their country for profit. IIRC Bolivia has started working on putting policy in place to keep from getting screwed over by large mining firms.

      "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."

    • no. There are tons of lithium everywhere (lithium is the 11th most common element in the ocean) in recoverable amounts (including the u.s.). As the price goes up, more and more supplies come on line. Not only that, lithium is not the primary cost of li-x batteries.

      read: http://gas2.org/2008/10/13/lithium-counterpoint-no-shortage-for-electric-cars/ [gas2.org]
  • by Alt_Cognito ( 462081 ) on Friday June 26, 2009 @04:24PM (#28487745)

    *groan* (yknow, being made of air and whatnot)

  • Energy Density Fears (Score:5, Informative)

    by Burning1 ( 204959 ) on Friday June 26, 2009 @04:29PM (#28487815) Homepage

    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.

  • Ten times the energy density of LiIon would be great, but LiS currently (as in, in products that actually exist) gives four times the energy density of LiIon. My laptop's battery lasts 3-4 hours now. Four times that is enough for me to use it all day on battery and just charge it in the evening. The problem is that they currently only last for about 30 discharge cycles, while LiIon is typically rated at 300. This seems like more promising technology for the next few years. LiS is mainly used in militar
  • Am I reading this wrong. If not, something tells me there is a lot more energy going into harvesting and purifying the Lithium than it is worth. If there is a need for an alternative I'd start here.

  • by flipmac ( 1586043 ) on Friday June 26, 2009 @04:49PM (#28488053)
    This thing 'theoretically' has more than 5kW-hr/kg, which is a big deal considering gasoline has an energy density of 46.9Mj/kg or 12.9kW-hr/kg. Coupling this new battery, when it exists, to a decent brushless DC motors, which are upto 90% efficient, then you'll have a purely electric car that can rival a gasoline powered cars in terms of power and range since IC engines are only 40% efficient (minus more energy that is absorbed in the transmission, etc). And I have a hunch that lithium is more abundant than crude oil. Downside is obviously with the higher energy density, the potential for fire/explosion is bigger. I don't know about you guys, but watching a shorted lithium polymer battery pack is very entertaining and dangerous.
  • I'll Believe It... (Score:2, Interesting)

    by rally2xs ( 1093023 )
    When I can buy one. Same sort of "good news" 2 years ago from Stanford when the "nanowire battery" was announced to be capable of 10X a regular lithium cell due to the nanowire construction of the anode. No mention that they also needed a cathode breakthru to achieve the 10X. Without a cathode breakthru, you get 3X. Big whoop. Good, but no cigar. An electric car needs the whole 10X. But guess what - where is that battery now? It's being "developed" by the researchers in question not at Stanford but
  • Air pollution? (Score:4, Interesting)

    by w3woody ( 44457 ) on Friday June 26, 2009 @04:51PM (#28488083) Homepage

    Any time chemicals interact with air, it strikes me there is the potential for air pollution.

    Is that the case here? I mean, in theory the chemistry may not result in pollution, but in the real world it only takes a fraction of a percent of the chemistry to take an alternate reactive path to result in unexpected or unwanted impurities...

  • Underwater use? (Score:4, Interesting)

    by Locke2005 ( 849178 ) on Friday June 26, 2009 @04:57PM (#28488173)
    Is energy density really a top requirement for submarine use? It seems to me most submersibles contain thousands of pounds of ballast anyway -- might as well carry heavy batteries. Plus "reacts violently to any contact with water" doesn't really sound like a property I would want in my submersible battery. Unless these are significantly cheaper or more reliable than li-ion, they don't sound like a win underwater. In cell phones and laptops, however, weight and volume are king, and any technology that stores more energy in less weight or volume will be an economic success.
  • If these are cheap to make and then I'd like to be able to pick one up on the way home from work and plug it in to my pool heater when I get home. Imagine heating your pool to 85F for the weekend for about $5.
  • by jameskojiro ( 705701 ) on Friday June 26, 2009 @06:31PM (#28489233) Journal

    I needed some batteries for the life support systems on my spacesuit, so i went and bought some of these new fangled Lithium-Air Batteries and they don't work worth a crap. They worked fine in the airlock but as soon as I stepped out on my space walk I was gasping for air as my life support system inexplicably shutdown.
    These Batteries are Horrible, just Horrible!!!! I have to trust my life to batteries for supplying me with Oxygen and keeping my temperature constant.
    Two space gloved thumbs down!

Air is water with holes in it.