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mobile phone battery specifications...

Discussion in 'General Electronics Chat' started by rocky06, Feb 1, 2010.

  1. rocky06

    rocky06 New Member

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    Guys.... i need some help in fetching informations about a mobile phone battery lik its impedance , current rating , to charge it how much current and power required & what should be the charger's impedance....etc..... where can i get those infos.. pls help me get those....
     
  2. MikeMl

    MikeMl Well-Known Member Most Helpful Member

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    Take back off cell phone. Look at battery. Battery voltage and chemistry should be printed on battery. Google that type of battery...
     
  3. RCinFLA

    RCinFLA Well-Known Member

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    Mobile phone batteries range from about 700 mA-hrs to 1200 mA-hrs. Smart phones have larger in 1000 - 1300 mA-hrs range.

    Rs of battery starts out about 0.15 ohms and degrades as it is cycled. At 300-400 cycle the Rs may double.

    Charging depends on manufacturer. Typically about 0.2 to 0.6 of mA-hrs rating current. Li-Ions need several safety failsafe measures for charging. The two most important are never charge a battery that is below 1.8 vdc and charger voltage must not exceed 4.25 vdc. A battery less then 3.0vdc needs a <0.1C trickle charge until voltage comes up to about 3.4 vdc.
     
  4. dave

    Dave New Member

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  5. Sceadwian

    Sceadwian Banned

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    Rc where'd you get that bit about a battery of less than 3.0vds needs a trickle charge till 3.4 volts? I'm curious as to the reasons.
     
  6. RCinFLA

    RCinFLA Well-Known Member

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    It is specified in IEEE1725 as a requirement but left up to battery manufacturer as the voltage limits. 3.4v is probably conservative. It is okay for most LiIon's to go to full rate charging at about 3.2 vdc. The trade off is how long to get a device alive after hooking up charger. An unload LiIon will not support much load until it gets above 3.6- 3.7vdc, but charger could support load sooner.

    Most of the safety items have to do with plating out Lithium and I believe the precharge is to ensure enough charge state uniformity to avoid the issue.
     
  7. Sceadwian

    Sceadwian Banned

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    Thanks for the reference, I didn't realize there were even any specs for battery charging lithium-polymer cells like that. I've bookmarked the standard for later reading. Nice to see some companies are at least trying to put this stuff down on paper standards.
     
  8. sakura88

    sakura88 New Member

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    I think that it can help you
     
  9. rocky06

    rocky06 New Member

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    thanks for ur comments guys... it was helpful...... now i got a new prob... can i boost current from from nA to some usable value..... say for lightin an array of LEDS or just to charge a li-ion battery... any feasible ideas guys.... hope u experts help me to solve this prob...
     
  10. Sceadwian

    Sceadwian Banned

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    ??? Regardless of voltage, nano amps are particularly useless, what do you have in mind? As you haven't actually asked a question yet, just some vague concept of converting nano amps to 'useful value' which makes no sense out of context of what you're trying to do.
     
  11. rocky06

    rocky06 New Member

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    oops.... sorry i was about to ask to boost uA to some usable value when the voltage is around 5 or 6v.....
     
    Last edited: Feb 4, 2010
  12. Sceadwian

    Sceadwian Banned

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    To increase current you'd need to decrease voltage. 5 times the current 1/5th the voltage, and that's with a 100% efficient converter, even good converters are only around 80-90% efficient and that's with more voltage headroom than you have. I think you'd be lucky to get 50% efficiency, and you'd end up with still not enough power to be useful for much.
     

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