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How Electric potential and potential difference work in batteries

  1. Apr 30, 2012 #1
    How is electric potential manipulated in batteries? Why do some batteries have a rating of 1.5v and others have ratings of 1.25v? I'm not looking for the answer of "its the materials used in the chemical reaction" because I know that.WHAT DO THESE MATERIALS DO DIFFERENTLY TO THE PHYSICS OF THE BATTERY (charge, distance, work, etc. )? I've learned that electric potential and potential energy rely entirely on position. For example the formula from electric potential energy is F * d and force is (kQq)/d^2 meaning that potential energy is (kQq)/d. Does this mean that a battery that has its anodes and cathodes closer together has a higher voltage rating compared to one is very long?

    Please answer in detail and again I don't want the "it's the materials used in the chemical reaction" answer to this question. That's not what I'm looking for because I already know that.

    Thanks for your help.
  2. jcsd
  3. May 1, 2012 #2


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    hi htttp! :smile:
    no, that's wrong :redface:

    a battery with two electrodes in a fluid will have the same voltage (electric potential difference) no matter how far apart the electrodes are
  4. May 1, 2012 #3


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    Just try it yourself at home. Connect the terminals to conductors and make the battery long. Then measure the potential with a voltmeter
    Last edited: May 1, 2012
  5. May 1, 2012 #4


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    Here's some detail:
    The materials used in batteries are electrolytes(solid or liquid). You know They dissociate when dissolved, or in electric field. The ions thus formed carry charge to/from the electrodes. The capacity of carrying charge by ions varies with the material you have used to dissociate into ions. And also some materials dissociate quickly and some produce more ions.
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