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Battery life 93% after 28 cycles ?

Discussion in 'Inspire 1 Discussion' started by ovisopa, Nov 1, 2015.

  1. ovisopa

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    Hello guys, I wanted to ask you if your batteries are having similar battery life as mine, both lipo's I have have 93% and 94% battery life after approximately 28 cycles. Is this normal ?

    I don't noticed any drop in flight time, it's almost as usual ~15 minutes with the big one and a little less with the small one. I always try to land when the 30% alarm kicks in, usualy from the alarm till I land it takes a few more seconds, while the battery can drop to 25% ,, very rarely it happent to land at 18%.

    I did the calibration at around 20 cycles, flown the I1 until it reached ~16% and than let it on until the lipo shut it self off.

    Thanks.

    PS. First flight with the I1 on 26.09.2015, total flight time until today 13h 19min, total distance 113km, total flights : 100

    Please update this doc with your battery statistics. THANKS !
    Inspire 1 Lipo Statistics - Google Sheets
     
    #1 ovisopa, Nov 1, 2015
    Last edited: Nov 11, 2015
  2. Scotflieger

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    You can expect a one percent drop in remaining Battery Life every 4-5 charges. That equates to 400-500 charges per battery although users may need to consider scrapping batteries before they get to zero life remaining.
     
  3. ovisopa

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    You guys that have the inspire for much longer time than me, how's the battery life on yours ? After 50 cycles .. after 100 cycles ? Can it last 100 cycles without scarifying flight time too much?
     
    #3 ovisopa, Nov 1, 2015
    Last edited: Nov 1, 2015
  4. Carlsberg

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    WOW, You just make stuff up that sounds good to you, (or do you have a source?) :rolleyes:


    ovisopa, I have almost 70 cycles on each of my 6 packs and only ONE of them shows less than 100%, (my only tb47 shows 98%).

    According to Scott's made-up theory, I should show less that 85% on each one.

    Scott, please don't trick the newbies into believing your far-fetched theories.
    Either give them facts, or give them nothing. Misinformation poisons these types of forums and really hurts the newbies trying to learn. :)
     
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  5. SultanGris

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    It will depend which firmware version you have installed. I'm using older firmware and after 36+ charges they still show 100% life, however I dont believe this is accurate. There is no possible way it will stay 100% forever. Usage lowers life, it's a fact. New firmware adjusts these readings and his observations may very well be correct. Doesnt mean they are correct or set in stone however, there are many factors and there is no possible way firmware can accurately predict battery life. Especially not dji firmware considering how buggy it's been to date, haha! It's meant as nothing more than a rough guideline and shouldn't be taken as set in stone accurate info, so don't get your panties in a twist and don't believe what your app says about your battery life because the one thing that's for certain is that no matter what firmware you're using it's not accurate.
     
  6. Carlsberg

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    From the first day I opened everything up I have never relied on firmware.
    Like in the "old days" (last year) I use a watt meter and I know exactly what is actually coming in and out of my packs. I guess only 1% of I1 owners have basic soldering skills, and only 1% of them use those skills. Too bad, I laugh that most of the population are clueless as to what is going on with their lipos, (like aliens most of you are to lipos) - lol

    [​IMG]
     
  7. SultanGris

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    Clearly you misunderstand, you either have current firmware installed or you don't. Whichever version is on your batteries determine what the app lists for battery life remaining. Older versions were very inaccurate and listed battery life at 100% even after 40+ charge cycles. Common sense tells you this isn't accurate info, repeated usage lowers overall life of a rechargeable battery. It isn't the same after multiple recharge cycles as when brand new and eventually it will fail. Therefore they changed the behavior/algorithms in the newer firmware in an attempt to more accurately display battery life and as a result it goes down with use. However it's not reasonable to assume this is accurate info either. Not all batteries are created equal and many factors will affect overall life. It's simply meant to be a rough guideline for the owner to use to give them an idea when to start watching battery behavior more closely to determine if it is no longer reliable and should be replaced. These batteries won't last forever no matter how good your soldering skills might be.
     
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  8. John Casey

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    I have one battery (TB48) that is stating 87% left and it's effectively dead because I get a warning when I fit it to the aircraft "Faulty Battery Cell" Only a fool would take off with it saying that so I don't. There is one cell that is 0.2 volts less than the rest so that's the problem. It happened when it had 50 charges which represented 13% of it's life - well it is really 100% of it's life. It happened after five and a half months but it was a few days over 6 months by the time I was talking to DJI about it and they wiped me - because it was over 6 months old. The funny thing is the invoice from the store I bought it from states 12 months warranty, which it is still within, but they sent me to DJI and they said warranty on batteries is 6 months. So I can use it as a doorstop or maybe a torch battery or to charge controllers in the field?? But watch out for that one because it catches you between charges and spells the end of a very expensive battery.
     
  9. SultanGris

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    Have you fully charged it and then fully discharged it till it powers itself off?
     
  10. John Casey

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    I have not fully (ie. dead flat) discharged it after charging, but I have fully charged it and discharged it by just using it to charge controllers. But that takes a long time. Incidentally, is there a good way to discharge batteries outside of flying the aircraft? But I have pretty much done that, yes. I'm trying to run it down to dead flat (or very close to it) at the moment and then I want to charge it from there to see what it reads then.
     
  11. ovisopa

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    Thanks guys, Carlsberg , SultanGris do you have the latest firmware installed?

    I want to understand if I'm doing something wrong, but I don't see what could be wrong in my actions regarding inspire Lipo's.

    I try to land right after 30% , I also have the voltage shown in top right corner and red was only when I discharged the batteries completely and I think once more but every time I land while the voltage is still yellow.
    If I know I will leave very early in the morning like 6AM , I'm charging the batteries in the night time, before I go to sleep. Maybe it happent a few times to keep the Lipo's fully charged for 1 - 2 days, but this I think once or twice. I keep them discharged (3.7 - 3.8v / cell) But since I got it I'm flying almost daily.

    I use the original charger, and only once, a week ago, I charged the lipo's in car with a DC to DC convertor (12v to 26v) which worked perfectly , the life of the lipo's was already at ~95% , I'm sure that is not the cause.

    50 Cycles for a 200 euro lipo is very low in my opinion, but I was also dissapointed with maxamps lipo which is pufffed at ~40 cycles, no better than naonotech's in terms of battery life, just in terms of weight/flight time (I remember the 6Ah 4S maxamp was 70 grams lighter than nanotech 6Ah)
     
  12. SultanGris

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    Flying the aircraft is the best and fastest way I know of. Hover around a foot or so from the ground if you think the sudden drop issue may occur, that way you don't risk a crash. Keep hovering till forced to land then just let the inspire sit until it powers off by itself. Let the battery cool and fully charge it, this should fix the issue but just in case your issue is due to a faulty battery and not this bug I would fly it carefully and close to the ground for the first flight after this reset procedure. Also change self discharge time to ten days in the app under battery info with this battery installed and powered on.
     
  13. SultanGris

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    I do not have latest firmware, and I wouldn't put much stock in the life percentage listed. I'd perform this reset procedure and set discharge time to ten days as well and look at the total mah listed when it's fully charged. How far off is this number from what it should be and did it change any from before the reset to after it? I would expect a battery to last well beyond 50 charge cycles. Have you done the reset procedure every 10 charge cycles like the owners manual recommends for battery maintenance?
     
  14. ovisopa

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    I don't know if this number is off or is something normall to drop like this, i did "calibrate" both lipo's at 20 cycles, the life percent didn't change only then, it's dropping constantly.

    Again, I don't feel the filght time is lower than when they ware brand new but that number seemed low after a month of use. If the lipo's will be ok for 200-300 cycles , I'll be very hapy. Very! :)

    I don't have a logbook but maybe it's time to get started and write down lipos information. Haven't decided yet if it will be hand written or digital, i'll go for digital because it can generate graphs easily to vizualize beter the evolution
     
  15. SultanGris

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    Near where it says battery life it should say a number followed by mah. A tb47 should be 4500mah, this number should possibly decrease as battery life goes down and might increase slightly after the reset procedure, that's what I was asking about, if you've noticed that number change at all and how much in which direction
     
  16. ovisopa

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    I uploaded now a screenshot for both lipos, the maximum capacity it is lower than the battery specs, I will monitor that from time to time, it will change only after a full discharge / recharge ?
     

    Attached Files:

  17. SultanGris

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    Not entirely sure as it depends on whether the battery has self discharge bug or just normal wear and tear, but that's about the only thing that causes it to possibly go up if it's the bug. Theoretically it should steadily get lower along with battery life after every 4 charge cycles I think someone said. Is one of those a tb47 and the other a tb48?
     
  18. ovisopa

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    Yes, one is TB47 and one TB48, both purchased at the same time with the Inspire 1, now a month ago.
     
  19. Carlsberg

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    I'm not sure why my question is so difficult to answer, maybe it's the way I'm asking the question. I don't care about battery percentages, discharge levels, auto this, auto that, all I want to know is what firmware you are on, ios or android, and version app you are using. This will be my 3rd and last time asking.
    Yesterday, when I asked for the 2nd time I told you that I was just curious, but you keep talking about battery percentages?
    I'm on 1.2.1.0 and wish I was back at 1.7 (which firmware are you on)?
     
  20. Scotflieger

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    For those of us not living in the dark ages and using the current firmware (1.3.x or later) and have carried out the recommended battery re-calibration, I can declare that my "theory" is backed up by the facts and my flight-by-flight battery records. The GO app reported battery percentage life reduces by 1% every 4-5 charges.
     
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