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How do battery works?

  1. Jul 29, 2009 #1
    Alessandro Volta uses a bimetallic strip (silver and tin) dipped in moist conductor (salty water) to make a battery.

    how can a potential difference occur between the two strips?

    in modern AA batteries, what do we use for the two dissimilar metals and the moist conductor?
  2. jcsd
  3. Jul 29, 2009 #2


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    The potential difference doesn't arise per se; it's a measure of how easily one of the electrodes gives up electrons and transfers it to the other electrode:

    A modern alkaline battery has electrodes made of zinc and manganese(IV) oxide (MnO2), with potassium hydroxide (KOH) as the electrolyte (and hence the reason it's called an alkaline--basic--battery).

    WARNING: do NOT cut cells open without knowing what you're doing, or wearing appropriate safety equipment! The black paste you have when you cut a cell open is actually both the KOH solution and the suspended bits of MnO2 anode.

    For more on a modern alkaline cell, see the Wikipedia article, or Duracell's handy-dandy information document:
    http://www.duracell.com/oem/Pdf/others/ATB-full.pdf [Broken]
    Last edited by a moderator: May 4, 2017
  4. Jul 29, 2009 #3
    hm i see.

    so it's more to do with the atomics of the two electrodes. :rolleyes:

    thanks for the warning. But i am more of a 'theoretical guy' if you like it. sigh...., i know i need to change this principle of mine soon. Maybe start with disassembling a remote control or a computer mouse...
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