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More than two terminals on cell phone battery

  1. Oct 5, 2007 #1
    Most batteries have only two terminals with symbols ''+'' and ''-''. I uderstand the function of two terminals. But almost all the cell phone batteries I have seen have more than two terminals. What is the reason for having more than two terminals? Please check this link:
    http://www.batteries.com/images/256x256/17753.jpg [Broken]

    Best wishes,
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 5, 2007 #2


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    Usually a temperature sensor ( check if one terminal is marked 'T' )
    one way of charging these batteries is to just supply current and monitor the internal temperature rise - then back off the current to keep it in control.
  4. Oct 5, 2007 #3


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    My cordless phone has 3 terminals. The two outer terminals are common to each other. This way I can place the hanset on the cradle either face-up or face down.

    Your 4 terminals might be so it can accept different chargers/phones. Or perhaps a discharge pair and a charge pair. I'm only guessing.
  5. Oct 5, 2007 #4


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    Some batteries also allow connections to each individual cell (or some subset of them) to allow for more careful monitoring and charging. I don't know if this is common for cell phone batteries, though.
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