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LiPo Battery Conditioing

Discussion in 'General Discussion' started by tapiot, Sep 11, 2013.

  1. tapiot

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    Is there a rule of thumb as to when to do a full discharge/charge cycle?
    I normally run my batteries until the red light flashes but that is not always the case.

    Is there some magic formula as to how many charge cycles you should do before you do a controlled dishcarge?
    I've been looking but info on the 'net is several years old and I have yet to see anyone come up with any rhyme nor reason.

    Thanks!

    Tim T.
     
  2. rilot

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    There's no hard and fast rule. Just monitor how many mAh you are putting back in to the batteries after each flight. If you always fly to the red light and then your batteries start taking less and less mAh and your flight times are reduced, it's time to replace the batteries.

    There is little evidence that doing full discharge/charge cycles does anything to prolong battery life. Just don't discharge them too far.
     
  3. marcus_canada

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    Pulling a full discharge/charge cycle on a Lipo doesn't do anything and can actually hurt them if you take it too far. Unfortunately, with the stock DJI Charger you can't do much but if you have a half decent Lipo charger it'll have a balance mode.

    This isn't the same as a normal balance-charge, but a more extensive operation. I do it with all my batteries once in a while and it's surprising how it lines everything up again. Takes a long time though, my last balance I did was on a 2650 3S and it took like 90 minutes !

    Well worth it though....
     
  4. BuyLowSellHigh

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    Marcus, can you give the make and model of the charger you use so i can look it up? I need to replace the stock charger from DJI. Thanks.
     
  5. rilot

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    I use a Turnigy Accucel-6 and it's excellent.
     
  6. ArshadR

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    Hi Marcus, can you provide more details on this full balance mode? How is it different from a regular balance charge? I'm using a HiTec X4 which has a balance mode, but it seems to be the normal balance charging option. Are there specific parameters to use? Thanks!
     
  7. marcus_canada

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    Yes, I have a couple of those chargers, they are awesome and at $22, irresistible.
     
  8. bumper

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    Lipo batteries don't like to be discharged too far, and have no "memory effect" like Nickel Cadmium batteries - so don't need to be cycled For longest life. Lipo's should not be stored fully charged, so it's preferable to charge them just before use or the day before.

    The best storage charge is near 3.8 volts per cell, or 11.4 volts for the 3-cell batteries used in the Phantom. The Turnigy charger "rilot" uses has a "balance charge" mode as well as a "balance storage charge" mode. The first has a cutoff voltage of 12.6 (full charge) and the storage charge cut's off at 11.4 with all cells nicely balanced (assuming the batter is good).

    The stock charger is a balance charger too, and will fully balance charge the batteries. It's just that it doesn't tell you a whole lot while it's doing this and it does not have the capability to do a storage charge or to discharge an already fully charged battery down to the correct voltage for storage like the Turnigy does.

    bumper
     
  9. marcus_canada

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    Funnily enough I have a Futaba X4 as well :D I don't use it in the field though, too big and bulky and with all 4 ports having cables hanging out the sides, it's just a bear.

    On a normal balanced charge the main red/black cables are used to charge the battery up to a certain point and at the back end of the charge the charge is administered through the taps. this is how the cells are balanced out.
    The Balance mode is a charge mode which only charges through the taps. The max charge current drops to 1Amp and the process takes ages. I tend to run this mode after a light discharge because otherwise it just takes soooooooooo long. The 60 minute timeout is replaced by a 90 minute timer (I think). I had to restart mine a few times due to timeout terminations.
    I had a pack which was out of whack even after a charge but the balance mode fixed it up nicely.
     
  10. bumper

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    At least on the Tenergy TB6B I have (that looks to be the same as the Turnigy) the balance charge takes about the same time, as the regular charge mode, but a bit more than the "fast charge" mode which tapers down at a different rate. I have mine set for 1C, or 2.2 amps and that is then the initial rate for charge, balance charge, or fast charge. The storage charge/discharge rate is 1 amp max.

    bumper
     
  11. ArshadR

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    Ah ok, thanks. Yeah I agree the X4 is huge and heavy and a pain in the butt to transport.

    Thanks for the clarification on the balance-only mode charging. I usually charge in "Balance" mode rather than the regular charge mode. I'm not sure if it's only using the taps or the black+red wires too. Takes about 45 minutes to fully charge, so I'm guessing it's the latter.
     
  12. tapiot

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    With the stock charger, I have charged batteries I just received as well as batteries I have ran down to the point of the Phantom ditching. I have always charged at one amp after the battery has cooled but I have never noticed it taking forever. Usually I am surprised at how soon they are complete. I am usually doing something else, keeping the battery in the protective bag during charging. Once it is complete, then I shift it to the bag in which I store fresh batteries.

    I use 3 bags, one for charging, one for discharged and one for charging. I also keep a record of each battery to make sure they all get equal use. I have 6 batteries and just bought two Thunder AC680 chargers. You can plug them into the wall or use your cigarette lighter socket in your vehicle.

    It will charge at rates up to 6 amps, can track data on up to 5 batteries, has USB connectivity to a PC and also has a discharge function. They are only single battery chargers but support multiple chemistries.

    I have not had opportunity to use them yet but will this week.

    Tim T.
     
  13. marcus_canada

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    One of the things I always look for and try to avoid is the Lipos which have a lot of MAH but are actually doubling up cells in the pack to achieve the high MAH.
    I mean, like many of the HK packs are like 3S2P (3 in series, 2 in parallel) so actually 6 cell. This gives high capacity and a hike in current delivery but the HUGE downside is that you can't balance the cells.

    As the paralleled cells have shared balance tap wires you cannot individually balance them. It is really common for the 2p type lipos to start getting puffy within a relatively short time as they prematurely degrade due to lack of balance. I have unloaded many a pack because of this :cry:
     
  14. Driffill

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    I've just started using an iMax B6 charger (probably a cheap copy). I also got a parallel charging board. It's handy for being able to bulk charge up to 6 batteries (I only have 4 ATM) but I don't have much faith in its ability to balance correctly while all 4/6 batteries are connected! Anyone else use this type of charger, I'd be interested to know your settings etc :)

    I've also got 4 little 12v 3s lipo chargers, only a small black box with 2 LEDs and charges via the balance plug, 800ma max I think (from memory), I might get into the habit of using these to balance to pack once the B6 has topped them up? Any thoughts on that.

    I'm getting quite a little kit together, have recently set up a tub to transport my phantom complete with props, cam FPV etc all attached, comes in handy to launch from too. The next thing I'll look at getting is a metal box/tub to charge/store my batteries, I might even mount the charger etc on/in it . . . . And a small 12v (~18A/h) dry cell, for charging lipos in the field, may also make its way into the kit :)
     
  15. jumanoc

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    You can't balance batteries by using a paralell board. This is great for charging. Sugestion is that every 4-5 charge cycles balance each pack individually. You'll get longer life and better charge / discharge rates.
     
  16. PJA

    PJA

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  17. Roadkilt

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    A great investment for $35 is the EOS Sentry, which is small, and gives total voltage, each cells voltage, max to min, and then automatically balances cells that are greater than 7/1000 of a volt apart. My cheap phantom charger and its numerous clones stopped balancing at a cell difference of 190/1000 of a volt. One new Phantom battery had large differences between the cells and I now always check the spread with the EOS device. great info in the field when you are about to send $1500 worth of kit into the blue and one of your cells is 80% charged and the others are 98%.
     
  18. jumanoc

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    Thats correct. The paralell boards allow to charge and balance batteries, but the accurated balance does'nt work if there are more than 1 battery plugged to the parallell board.

    Paralell board provides an AVERAGE cell status to charger not data from each cell individually as when you only connect and balance 1 battery. That said, if you plug 6 batteries to paralell board ans select BALANCE on charger, the charger will set the status according to the 6 average charge, even you can set a worst scenario if charging /balancing different C rate and mAh packs at the same time. Be careful with this mix specially if you have a 0.1v difference between cells. :shock:
     
  19. marcus_canada

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    Yea, I won't use these boards ever, you're just asking for trouble. I'd rather charge a lipo without balancing at all if I'm in the field and need batteries quick, then do a balance charge later at home
     
  20. tapiot

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    The red and black wires are used for the "constant" current mode, around 80% charged.
    Then, with a balanced charger, it shifts to constant "voltage" mode and each cell is charged through the tap.
    The contacts in the connectors and the small wires are due to very little current flowing.

    Tim T.