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Whats your battery life? still using it?

Discussion in 'General Discussion' started by kcmusa, Aug 19, 2016.

  1. kcmusa

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    As I watch my battery life, age. I wonder how far I can take it before its unusable.
    my lowest now is 92%, have not seen lower flight times.
    How far can you go?
    what is your battery life and have you seen shorter flight times?
     
  2. Nate-xt

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    ive had mine for almost a year and have not seen any battery life drops.
     
  3. longdog

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    Try to condition your batteries every 20 flights.
    Fly down to about 20%. Cool down. Then leave bird on and stationary or idle until at 8%. Let cool down.
    Then charge all the way up.
    Done!
     
    BigAl07 and ROD PAINTER like this.
  4. Pharm

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    DJI no longer recommends the 8% discharge routine. Some people still swear by it, though.

    See this thread (posts #10 and #13):
    P3P Battery Discharge Question
     
    #4 Pharm, Aug 19, 2016
    Last edited: Aug 19, 2016
  5. longdog

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    Interesting. So it seems there is no harm in doing deep discharge, but no benefit either?
    Has DJI confirmed that the batteries are fine and stay 'smart' by not doing deep discharge?
     
  6. Pharm

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    I've seen some anecdotal evidence that they do but I really don't know.
     
  7. longdog

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    Hmmm. Okay then.
    I've always been in the school of thought that it's good to condition batteries. I know it's more so important with Nicad or Nimh batteries than Lipo batteries. But with lipo, I've not heard of anything bad happening when following general best battery practices. (Fully charge and discharge mostly - store with moderate charge; make sure they never fully discharge)

    It's the Nicad and Nimh that suffer from "memory" issues. Doing things like discharging completely, overcharging, or even using only half way then charging part way was damaging to the battery integrity. Lipo has largely overcome this so its okay to charge to 100%, run down to 50% charge to 87% then run to 11% then charge to 77% etc...
    Nicad and Nimh this would quickly degrade the battery performance and longevity.

    Lipo is most definitely an awesome technology and is extremely forgiving. Those who have old school RC battery experience will know what I'm talking about.

    I just don't see the harm in following some type of maintenance regimine for Lipo. It's possible there is not any advantage and I'm doing for no good; I'd just doubt there is any adverse effects.
     
  8. yorlik

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    One could argue your comments...

    1) Lipo life is being proven to be longest when NOT discharged deeply. Look at the 1000's of small almost AA size 18650 cells used to power the Tesla car: studies showing folks who are not running down to much less than 50% charge are at 7-8 year life with like new batteries, and going strong well after that. From my lipo EV car experience, I disagree with your comment "discharge mostly." My 108 cells were like new for 4 years: I then decided to allow fast accelerations, 0-60mph in 7 seconds in a chevy equinox (250amp peaks upped to 450amps) and I harmed 4-5 cells in a few months time. I have had some extensive discussions with PHD Dr. designers of lipo cells, and all have agreed that small discharges will make them last almost forever.

    2) Again, running lipos down to 11% is, in my experience and study, detrimental to longevity.

    3) Keep i mind the 'discharge to 8%' dji suggestion had NOTHING AT ALL to do with lipo batteries or their life: it was simply a method they used to re-calibrate their internal BMS (battery management system IC) so it read correctly - nothing at all to do with making the lipo last longer! It only shortened life but in P2 days was required to recalibrate the mah readings.

    If one was willing to only fly from 100% down to 70% minimum, ones lipos probably would last for 10-15 years before significant degradation set in (600-800 cycles). But to most people that trade off is not worth it.

    Some data to support my comments:

    What's the life expectancy of a Tesla Model S battery, and will there be a replacement plan of some sort? - Quora

    Let's see if a typical life curve based on how far you discharge shows up:
    upload_2016-8-20_14-15-53.png
     
  9. longdog

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    Interesting. One feels that you know a few things about batteries and may have some points.
    I'm a believe it when I see it guy, and might do a little experiment.
    I've got two DJI batteries and they are fairly close in age. One I'll run and condition on the healthy drone schedule; the other I'll just run normally. Charge to 100% and land with 20% - 50%.
     
    #9 longdog, Aug 20, 2016
    Last edited: Aug 22, 2016
  10. sinxa

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    Ok guys up there. . . So what is your battery life right now? Are you still using it? Is everything just fine?

    I only have 1 battery for my P3s, but unfortunatelly it was dead after the 7th charge cycle. I send it to the dealer and they lend me spare battery while waiting my battery being analyzed or repaired or replaced. So right now i am using the spare battery with 95% battery life and 22 cycles when i recieve it. And it become 90% battery life 40 cycles today.

    Sent from my SCL23 using PhantomPilots mobile app
     
  11. regdawg

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    Yeah I only currently have 1 battery for my P3P. My flights are only usually a batteries worth anyway which is why I didn't purchase another, at least not yet. I couldn't justify spending $100-$150 on an extra battery when I probably won't use it as often. If I can get a year or more of good life out of my 1 battery, I'm all gravy.
     
  12. Hopeful

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    Hi, thanks for all the info there. The limiting factor for me with rc lipo batteries is the fact that they puuf,
    and physically will not fit. These are not DJI batteries, but no-one has mentioned if DJI batteries can puff. They
    are tight fit, and will easily jam if they puff. I note that my original P1.1.1 3s batts have Not puffed,
    but have lost their capacity. Some brand X batteries have puffed within a few cycles, and I am
    hoping that the P3 battery wont go that way! Has anyone had puffing problems with DJI batteries?
     
  13. sinxa

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    So far, no. . . I don't know for sure later. . . The most problem we have in P3 are : swollen, unbalanced cells, and voltage drops. From some sources i've read that it might happen on aged P3 batteries. Cmiiw.

    Sent from my SCL23 using PhantomPilots mobile app