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World's First Battery Fueled By Air

Hugh Pickens writes "The Telegraph reports on the revolutionary 'STAIR' (St Andrews Air) battery could now pave the way for a new generation of electric cars, laptops and mobile phones. The cells are charged in a traditional way but as power is used an open mesh section of battery draws in oxygen from the surrounding air that reacts with a porous carbon component inside the battery, which creates more energy and helps to continually 'charge' the cell as it is being discharged. The battery has a greater storage capacity than other similar-sized cells and can emit power up to 10 times longer. 'The key is to use oxygen in the air as a re-agent, rather than carry the necessary chemicals around inside the battery,' says Professor Peter Bruce of the Chemistry Department at the University of St Andrews. 'Our target is to get a five to ten fold increase in storage capacity, which is beyond the horizon of current lithium batteries.'"

13 of 205 comments (clear)

  1. Question by MyLongNickName · · Score: 5, Interesting

    Would there be any danger of using this in a confined space? Any clue on how much oxygen this thing is churning through?

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    1. Re:Question by narfspoon · · Score: 5, Funny

      Would there be any danger of using this in a confined space?

      Only if you had beans for dinner.

    2. Re:Question by Tweenk · · Score: 5, Insightful

      According to the article the lithium is oxidized to Li2O2, so 1 mole of lithium takes half a mole of molecular oxygen during discharge. If the battery contains 100g of lithium (a large laptop battery might contain this amount), a total discharge would need

      100 g / 6.941 g/mol * 0.5 * 22.4 dm3/mol * (100%/20%) = 806.8 l

      of air, or less that one cubic metre. The second figure is the atomic mass of lithium, the third is the ratio of the stoichiometric coefficients of oxygen and lithium in thhe reaction, the fourth is the molar volume of ideal gas, and the last is the factor from oxygen concentration.

      So unless you are in a coffin this is not a risk.

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    3. Re:Question by Tweenk · · Score: 5, Informative

      Addendum: the same amount of oxygen would be liberated when charging. It could be a problem if you decided to charge it in an air-tight box, but under normal conditions it won't be a problem.

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  2. Powered by Air? by newcastlejon · · Score: 5, Funny

    Or is just hot air?

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    1. Re:Powered by Air? by sakdoctor · · Score: 5, Insightful

      Nice headline Taco.
      This is "fueled by air" in the same way an internal combustion engine is.

      This is a Lithium battery. Why isn't Lithium in TFS?

    2. Re:Powered by Air? by morgan_greywolf · · Score: 5, Informative

      Agreed. It's not even the first battery powered by air in this manner. As Taco ever heard of zinc-air batteries? These are commonly used in, among other things, hearing aids.

  3. Any side-effects or drawbacks? by BadAnalogyGuy · · Score: 5, Interesting

    Sometimes things sound too good to be true. Risk-free money smuggling from Nigeria. Enormous genitals from a few pills. Whiter teeth using only household chemicals. Articulate and clean presidential candidate who seems like he can fix anything.

    Extending the life of batteries using the air sounds like a great thing. But what is the hidden problem that we are overlooking here? Will the chemical reaction of the battery and oxygen deplete the batteries faster than standard LIon? Are the batteries heavier? Output less power? Require usage patterns that aren't typical for normal users?

    It just sounds too good to be true.

    1. Re:Any side-effects or drawbacks? by confused+one · · Score: 5, Informative

      The carbon is only used as a reaction matrix and an electrode. It's a lithium air battery. The oxygen reacts with the lithium during discharge to create lithium oxides. During recharge the oxygen is liberated and returned to the atmosphere.

  4. Almost there by cat_jesus · · Score: 5, Funny

    Now we just need to create a battery that recharges using CO2. That would be the invention of the century.

    1. Re:Almost there by MyLongNickName · · Score: 5, Funny

      You are in luck.

      (I love having to wait five minutes between posts)

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  5. Re:Wow. by moon3 · · Score: 5, Insightful

    /. gets this kind of miracle technology often, most of the stuff has also an "Achilles heel" that prevents real worlds deployment.

    This might be an exception (hopefully), but until you can get one off NewEgg people stay cool and cautious.

  6. More informative article by Tweenk · · Score: 5, Informative

    There is next to no information in the first article... this one is much more informative:
    http://www.theregister.co.uk/2009/05/19/lithium_oxygen_stair_battery/

    The concept (taking one of the reagents from air) is not new. There were zinc-air batteries for decades, and they are widely used. They have one of the highest energy densities of all types of commercially available batteries.
    http://en.wikipedia.org/wiki/Zinc-air_battery

    Seems like four years ago somebody even figured out how to make them electrically rechargeable (before that, the usual method of recharge was to replace the zinc plates and remove oxide waste, which was facilitated by cell design).
    http://www.eetimes.com/news/semi/showArticle.jhtml?articleID=164903727

    However, if those new batteries use carbon instead of zinc, they might have a higher theoretical upper bound on energy density. It looks like they're using graphite-lithium intercalate for the negative electrode (a standard thing), and the positive electrode is essentially a combined catalyst/adsorbent for Li2O2 which forms during electricity generation.

    CnLi ---> Li+ + Cn + e
    2Li+ + 2e + O2 --cat.-> Li2O2

    Note that the first article is rather bogus: O2 does not "recharge" the battery, it is only a reagent.

    I'm not familiar with the cost breakdown for the components of Li-ion batteries, but lithium seems like a major contributor, so this might not be much cheaper than the traditional Li-ion.

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