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Battery lif vs real life span

Discussion in 'Phantom 2 Help' started by Gustavo Aguiar, Feb 20, 2016.

  1. Gustavo Aguiar

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    Hi guys I'd like some help about DJI P2 battery life. I have one that after 31 flights has 90% of life.

    I have read a plenty of articles and watched some videos about not flying bellow 90% of life, but I wonder if DJI wants us to buy more batteries or the battery is really almost dead.

    I have flight other day and seems to be OK. I'd like to hear a bit of you about it. I'm not very good about electricity concepts, but this battery seems to be OK, when it's fully charged the cells are like this:

    Cell 1: 4139mV
    Cell 2: 4138mV
    Cell 3: 4135mV

    Overall voltage is 12412mV and the current capacity is 5076mAh and shows the actual full capacity as 5153mAh.

    Do you know if I can trust those indicators or it's better to retire this battery?
     
  2. jason

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    That's a problem with what you read in these threads everyone has an opinion whether right or wrong. .What you should be concerned with is the condition of the battery itself not the percentage of life.
    Battery Warning.jpg

    The only way to really know what condition your batteries are in is to pop them into your P2 and connect the software.As you can very well see this has 90% life and was 15 months old but has damaged cell error message. Check current and charge readings there's the real problem. Did the battery fly the P2 yes. Did I return and change batteries better believe it. I also have two batteries which are two years old that have 87% life cycled 47 times That I do not use because there only good for 6 minutes of flight and auto land at 15%. If i landed at 30% like most do the light would be around 3 minutes in the air.

    Always check your batteries after charge and before you leave for a flight and if you have an FPV with telemetry installed keep an eye on the batteries performance Here a video I recorded when a battery hit critical voltage of 10.65 at 100 feet because I wasn't paying attention until it was almost to late. Enjoy!!
    .
     
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  3. Gustavo Aguiar

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    Thanks for your reply, Jason. You told me exactly I was wondering, but not sure about it. What I have seen and understand from the screenshot you posted is to pay attention to the mAh (besides the assistant alert), right? The design capacity is 5200mAh, the Full capacity was 2281mAh and the current capacity is 2801mAh 97% charged, but the cell voltage is OK.

    It's 90% life but the mAh seems to be OK and no alert about damaged cells. What do you think?

    Check the screenshot I have uploaded (or the link Dropbox - 160214 - b01.PNG).
     

    Attached Files:

  4. jason

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    The voltage for each cell may look good but if the current isn't then the battery is worthless as it is in the screen I posted.
     
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  5. jason

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    Here's what a 2 year old battery looks like before and after charging.
    Barttery #2 before charging.jpg Barttery #2 after charging.jpg
    If you noticed the discharging times didn't change and it should have
     
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  6. N017RW

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    It's been surmised in the past that until 5200 mah has been 'drained' it will not increment.

    Is that no longer seen as the case?
     
  7. jason

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    That seem to be the case with this battery. But I only charged it as demonstration as it is 2 years old and had no intent to fly with it.
     
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  8. Gustavo Aguiar

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    Thanks!