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Battery Output

  1. Feb 1, 2014 #1
    If you study a DC signal under an appropriate scope, you can see the switching transitions ; a pwm signal.

    But if you examine a battery, no matter how high temporal resolution you reach, you see a dc signal.

    What might be the explaination for this? electrons are being generated by a chemical process in battery and these reactions are very fast so the switching frequency of battery can be very high. What should be the approach to this problem?
     
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  3. Feb 1, 2014 #2

    phinds

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    Huh? WHAT "switching frequency" of a battery? I don't understand what you mean.
     
  4. Feb 1, 2014 #3
    Smallest possible charge is 1 electron thus there should be some sort of rate to generation/conversion.
     
  5. Feb 1, 2014 #4

    davenn

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    rate to generation/conversion of what ?
     
  6. Feb 1, 2014 #5
    Ion transport rate.
     
  7. Feb 1, 2014 #6

    ZapperZ

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    Let join the chorus here: what ion transport?!!

    By now, you should have a sense that you are not explaining yourself very well here. The first 3 responses are us trying to figure out what exactly it is that you are talking about.

    So how about starting all over again and put some effort into framing this as best as you can.

    Zz.
     
  8. Feb 1, 2014 #7
    I am sorry, trying again.

    When you connect a resistive load across terminals of a battery, a direct current will start flowing ; meaning specific amount of electrons propogating per crosssection but how about the repetition rate of this process? Inside the battery ions are being transported and there is a rate of this phenomena.
     
  9. Feb 1, 2014 #8

    Drakkith

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    This ion transfer rate is equal to the rate of electrons flowing through the circuit between the terminals of the battery. If it wasn't a net charge would build up and prevent any further current flow from one terminal to the other.

    Note that there is no switching involved here. The ions do not flow through the circuit, but through the electrolyte.

    From wiki: http://en.wikipedia.org/wiki/Electrochemical_cell

     
  10. Feb 1, 2014 #9
    Thank you for the information.
     
  11. Feb 1, 2014 #10

    rcgldr

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    The transitions within a battery at the atomic level happen at a very fast rate and they overlap. There aren't any real world instruments sensitive and fast enough to see the very slight and very fast flucuations in the output of a battery. From a practical standpoint, the output of a battery can be considered to be continous.
     
  12. Feb 2, 2014 #11
    That's what I was talking about but didn't wanted to push more after I observed that I could'nt express myself to majority efficiently.

    The main phenomena responsible is;
    http://wikipedia.org/wiki/Proton_coupled_electron_transfer

    And it's being driven sequentally, but they overlap as you say and that's the main problem. If you study the problem further you are going to realize that there exists some sort of 'switching' indeed, and it should be around on the orders of ~E+24 due to fundamental properties of Weak Interaction.

    Maybe this problem can be modelled using QM more precisely, approach should be right.

    As of today, mankind is on the orders of E-18 which is far from probing E-24.

    Thank you.
     
  13. Feb 2, 2014 #12

    Drakkith

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    1. What is this switching problem?

    2. I don't see how the weak interaction applies in this situation.
     
  14. Feb 2, 2014 #13
    1.No problem, solved.
    2.I can't say that I understand fully either. But I can say that it's much faster than emf because can't see the propagation delay between electrolytes. Distance between them is 6cm so it would take 200ps minimum, I have a scale of 40ps on my scope but still get a phase difference of 0.
     
  15. Feb 2, 2014 #14

    Drakkith

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    I can confidently say that the weak interaction has nothing to do with this.
     
  16. Feb 2, 2014 #15

    ZapperZ

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    And on that note, this thread is done.

    Zz.
     
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