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Weird battery power issue

Discussion in 'Pro/Adv Discussion' started by Garrie, Oct 9, 2015.

  1. Garrie

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    I own 4 P3 batteries. On my last flight, I used up all 4 batteries, flying on each till around 20% before flying my bird home and replacing with a fresh battery.

    I have a drone meet tomorrow so I decided to charge my batteries. Before I plugged all 4 batteries into my charging hub(DJI), I click each battery to confirm that they were all on low power. All showed one green led flashing with each button press.

    When I started charging the batteries, I noticed that the hub only cycled within 3 of the 4 batteries. The lone battery that didn't go through the hub's pre-charge "checks" may or may not have been seated completely into the hub, I'm not sure. But after turning off the hub, ensuring all four batteries were securely snug in the hub, I turned on the power to the hub again.

    Once again, that particular battery was skipped in the pre/charge checks. I took out that battery and click the button once.

    It showed 4 leds lighted up! Full power?! That's impossible.

    I brought it back to my room and tested it in my P3. Turned on my remote and connected my phone and launched the GO app. Battery power indicated 15% now.
    This is the screen grab from the battery info page at the moment.

    ImageUploadedByPhantomPilots - DJI Phantom Forum1444367983.220466.jpg

    Could anyone find out if anything is wrong with the battery? Does the "100%" mean anything even though my battery clearly wasn't at 100% power at that point?

    Anyway I decided to run the engines without props for a while. Brought the remaining power from 15% to about 13%.

    Plugged the battery back into the hub and now all 4 are charging as per normal.

    Weird.
     

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  2. Andrea

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    I am not a battery expert, but the 100% battery life you were reading refers to the total life of that battery, and I mean the total number of charge/discharge cycles. 100% means that probably that battery is still pretty new, and has a few number of flights on it's back.
    Instead you can clearly read the remaining power which is the spare capacity of the battery: it shows 671mAH vs. 4475mAH completely charged, which is approx. 15%. The P3 and the GO app are showing all the datas correctly.
    I'm not sure what happened with the battery... maybe something messed up the internal readings of the electronics of the battery for a moment (electronic belived the battery 100% charged and that's why all the 4 leds were lit when you pressed the power button and that's why electronic avoided battery from charging).
    I guess you were able to charge it in the end... but if this strange behaviour should happen again I would be concerned with that battery.
     
  3. Garrie

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    Yeah. I saw the data and was pretty sure that the battery was truly at low power. Just confused as to why the battery would show full power.

    I wonder if it could be due to it not being seated completely in the hub or seated partially. And then somehow it screws up the battery calibration.
     
  4. Andrea

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    Honestly that was my first thoughts.
     
  5. Watchara Bhutiyodhin

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    It is Battery Life, that meant this batterry still able to charge to 4475mAH. If Battery Life go down from 100%, such as 80% that meant this battery able to charge to 80%x4475mAH = 3,580mAH.

    The Power is ratio from Remaining Power / Total Capacity, on this battery = 671 / 4475 = 15%.
     
  6. Garrie

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    Yup I can infer that it is truly 15% at that point from the values shown in the pic. I'm just wondering what was the cause of the battery showing it at full power
     
  7. RoyVa

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    It was showing the. Remaining battery life as still being able to go to 100%. That is a battery life remaining indicator.
     
  8. invinciblevin

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    If this happens press the battery once then press and hold and turn it on. Whilst on the hub this forces a charge. Works when battery is above 75% which would not normally be charged by the hub. The hub will initiate a charge for anything <75%. So if your hub for whatever reason skipped the charging on one of your four batteries or even f you want to top up the charge from 94% to 100% (as I do like to have fully charged batteries) use these steps.
     
  9. invinciblevin

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    If you read the question he was talking about the hub.