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How much is 100%? [answered]

asked 2014-02-06 10:26:39 +0200

cy8aer gravatar image

I just wonder how much the battery is loaded when 100% is shown:

  • 100% but no blinking (battery full) status
  • 100% and blinking status just started
  • 100% blinking but loaded the battery over night

for me there is definitely a difference with just blinking and overnight (faster lowering to 99-97% when just blinking)

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The question has been closed for the following reason "the question is answered, an answer was accepted" by JSEHV
close date 2016-02-01 15:06:32.136944

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I have also thought about why the charging level does not drop from 100% to 97-98% as its normal for battery to lose some of its power after reaching max power level and then start recharging again. Or is it just for making sure to anyone the device is actually fully charged

TimTTK ( 2014-02-06 19:15:11 +0200 )edit

I have assumed that different speed of dropping to 98% is caused just by that if the charger has actually been charging. After battery is full the charger gets disabled until the battery charge drops a bit. If I disconnect while it is just charged full, it takes longer for battery charge to drop to 98%. I don't have much insight on how these batteries actually react and how Jolla actually measures the battery level, but sycling between 99% and 100% over night might have effect on how much energy is stored to the battery.

TemeV ( 2014-02-07 00:20:39 +0200 )edit

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answered 2014-02-06 22:49:57 +0200

attah gravatar image

updated 2014-02-06 23:06:18 +0200

I would assume they use the voltage to measure the charge level. And while you can still squeeze in some milliamps when at full/desired voltage.. you can't tell the charge level by the voltage anymore. There can still be some guesswork and "dead reckoning" employed.. but it's kind of bound to be at least a little bit off.

That might be the difference between blinking and not.. and it would definitely explain why it would drop the first few percents faster.

Read more here to get an idea: http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

NB: This is pure speculation on my part.

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Very useful info about how Li-ion batteries work. Full discharging and overcharging must be avoided to keep battery in good shape. Not like in the batteries seen in past...

TimTTK ( 2014-02-06 23:01:14 +0200 )edit

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Asked: 2014-02-06 10:26:39 +0200

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Last updated: Feb 06 '14