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Thread: Why Lithium,not Hydrogen in batteries?

  1. #1 Why Lithium,not Hydrogen in batteries? 
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    Could somebody explain why there is
    Li-ion battery but no Hydrogen-ion battery?
    Hydrogen ion is even smaller and should have
    greater electrochemical potential then Li.
    And even more it's much cheaper.


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  3. #2  
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    There currently is no cheap and efficient enough alternative to the proton exchange membrane used in hydrogen cells. They are also currently much larger than is practical for small electronics.


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  4. #3 Exploding Li-ion batteries 
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    Here is an article which explains the cause of explosion of Laptops which contained Li-ion batteries.

    http://electronics.howstuffworks.com...n-battery2.htm
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  5. #4  
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    But will such type of chemistry work at all?
    Could we create hydrogen ion batteries where
    lithium ions will be substituted by protons?
    I think such type of chemistry would be especially good for nanowire battery because
    protons are much smaller the Li ions and will
    cause cracking much less.
    I've read that NEC created some proton-polymer battery but it works rather as supercapacitor.
    What could be real chemical potential of protons in comparison to Li ions?
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  6. #5  
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    Sorry for diletant question:
    If in Li-ion battery positive ions which already seem to miss electrons just
    move from one material to another,where is electrons taken from to run in external circuit?
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  7. #6  
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    In Li ion batteries you have a chunk of solid lithium metal and a carbon electrode sitting in an electrolyte. When the battery drains, the solid Li (which is in the zero oxidation state) is oxidized to Li+ atoms that float around in the electrolyte and eventually embed in the carbon electrode. When you recharge the battery, you force the Li+ ions out of the carbon electrode and reduce them back into solid Li and deposited back onto the Li electrode.

    You couldn't do this with H+, because there is no such thing as a solid hydrogen electrode. You would have to reduce the protons to hydrogen gas.
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  8. #7  
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    In Li ion batteries you have a chunk of solid lithium metal and a carbon electrode sitting in an electrolyte. When the battery drains, the solid Li (which is in the zero oxidation state) is oxidized to Li+ atoms that float around in the electrolyte and eventually embed in the carbon electrode. When you recharge the battery, you force the Li+ ions out of the carbon electrode and reduce them back into solid Li and deposited back onto the Li electrode.
    Are you shure?In this case I don't understand what is
    difference then between Li-Air and Li-ion battery.In all discriptions about Li-ion battery they describe it as intercalated Li ions which just migrate between anode and cathode.On anode they usualy have Li ions which are intercalated in graphite.
    This is charged state of battery.When battery discharges,ions just migrate from anode and intercalate in cathode (usully Co2,MnO2 etc.).When it is charged ions migrate back to graphite absobtion cathode.It seems Li-ion battery whas developed intentionaly to avoid problems associated with Lithium such as ignition or chemical reactivity.I don't understand if they still have solid lithium in battery,what is sense to bother with all those porous electrodes?Maybe you have some pictures of this process?It's very difficult to understand from wikipedia article http://en.wikipedia.org/wiki/Lithium...ectrochemistry because in the begining they write that Li-ion battery has carbon cathode.
    But later that it has porous carbon anode and CoO2 cathode.I thought that anode
    and cathode can't change places.I know that they are trying to make improvements in Li-ion anodes swithing to Silicon because it could absorb more Li ions.So where do we have a ckunk of metal Litium if neither on catode or anode?And what is sense to call batery Li-ion,if in any battery we have proces of a metal dissociation to ions which travel through an electrolyte?Is Li-air battery not "ion" then?
    Could somebody provide some pictures of the process, it could be very helpfull!
    I found some patent that describes battery with proton intercalation process:
    http://www.patentstorm.us/patents/48...scription.html
    Athough I don't know whether it will work or not.
    Also I'm curious to know if it's possible to make battery which would generate
    electric potential similar to thermopower without electrons moving in external circuit.For example ions just migrate from one host material to another.
    Antislavery
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  9. #8  
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    Quote Originally Posted by Stanley514
    Are you shure?
    Well, that's how normal Li ion batteries work. I can't promise that there aren't other freaky types.
    In this case I don't understand what is
    difference then between Li-Air and Li-ion battery.
    I don't know what a li-air battery is, so I can't tell you the difference.
    In all discriptions about Li-ion battery they describe it as intercalated Li ions which just migrate between anode and cathode.
    The anode is solid Li, the cathode is carbon with intercalated Li+ atoms.
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  10. #9  
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    The anode is solid Li, the cathode is carbon with intercalated Li+ atoms.
    If they have solid Li anode and only lithium positive ions on cathode,where those electrons go after they complete their run over external circuit :? ?
    What do you exactly mean under Li+ atoms?I thought that only ions could have
    prefix "+".It means they miss their external electrons.
    Silicon, which stores ten times more lithium than graphite, allows a far greater energy density on the anode, thus reducing the mass of the battery.
    http://en.wikipedia.org/wiki/Nanowire_battery

    If they have solid Li anode why to bother with Silicon nanowires?

    In manual how to charge Li-ion bateries they describe plating of metalic Lithium on anode as deseaster not as something normal:
    http://www.batteryuniversity.com/partone-12.htm

    Probably my greatest confusion is how exacly process of intercalation works.
    I found formula of reaction:

    С +( xLi+)+( xe-) → CLix

    But if Lithium ions unite again with their valent electrons what is sense to call it
    "ion intercalation"?Why not just Li atom (neutral) atom intercalation?
    Antislavery
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