Fully charged - or not?


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  1. NeilW

    NeilW Member This Topic's Starter

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    I wondered if anyone else had observed this and come to the same conclusion....

    Obviously, when the Desire is fully charged, the LED goes from orange to green and I assume it starts trickle charging to protect the battery...

    HOWEVER, if a "high current" application runs when the phone is trickle charging (even just having the screen on - like after the alarm has gone off) and the phone is drawing more than the trickle charging supplies, the battery supplies the rest... Thus, when you unplug it, the battery monitor re-evaluates the state of charge and it is (sometimes) way below 100%.

    So, I've got into the habit of a) blanking the screen again after the alarm has gone off b) unplugging the phone for a couple of minutes and then plugging it back in to check what charge it really has (and giving it a chance to charge up to 100% again.

    I suspect there is a bug lurking in there in not switching back to full charge rate if the battery has lost charge....

    Neil (unbranded UK Desire running Froyo)
     

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  2. Meh

    Meh Well-Known Member

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    +1 same issue here, have charged it overnight, unplugged it in the morning and had the battery at around 90%. Seems to be quite common looking on other forums. I'm on 2.1, O2 UK branded (I assume locked too) handset.
     
  3. Mubble

    Mubble Well-Known Member

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    The battery stops charging when it reaches 100%. When it drops down to 90% it kicks in again and charges back up to 100% - and so on.

    It's quite possible to unplug the phone after many hours of charging and for it to only be at 90%. If this happens and you then unplug it and run a power sapping app, it's quite feasible to be at 85% a few minutes after unplugging.
     
  4. Eris Ed

    Eris Ed Well-Known Member

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    This normally happens when the phone is left on charge overnight. When the battery gets to 100%, charging stops, so when you wake up it might show 90-99%. reconnecting usually tops-up to 100%.

    During the day I usually charge my phone and unplug it when the light turns green. Often the battery level shows 99%. Reconnecting for a further 30 mins gets it to "Fully Charged", and it stays like that for a while until I start using the phone.
     
  5. ukzen

    ukzen Well-Known Member

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    The question here is why?,do you know of any other phone that charges this way ,i dont !,never had one that reacts this way and i`ve had loads.
     
  6. Meh

    Meh Well-Known Member

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    Thanks for the explanation. It's odd, I've also never had a phone that charges this way. It's no biggy for me though if it's meant to be this way, so long as my handset is ok I'm happy.
     
  7. Hadron

    Hadron VIP Member VIP Member

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    It is "normal" for a Desire, but IME peculiar to the Desire.

    It's not just that it stops charging at 100% and then doesn't restart until it drops below 90% though. When off charge mine normally only drops 2-3% overnight, whereas it can "drop" as low as 90% when left plugged in! So there's some accelerated discharging going on here, because otherwise I would never see it below 97% when plugged in overnight.
     

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