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  1. #1
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    What charging cycle to use?

    My charger has lipo charge, balance charge, fast charge etc?? Just wondering what charge to use?? My mate who has the same charger just uses balance charge and says it takes the same amount of time as fast charge?

    Setting 2s 5000mah lipo to charge at 5 amps??

  2. #2
    RC Qualifier Whitecobra's Avatar
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    Balance charge LiPo's.
    1997 White Mustang Cobra its not a RC!

  3. #3
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    Also charging limit is set to 5000mah. That is what always stops the charge? Should i have it set to 5000 for a 5000mah battery or have it set higher and stops when full??

  4. #4
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    Check the voltage if it triggers 5000mah stops. Just to be sure your charger is not over charging.

  5. #5
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    Illusion, Im not sure what you mean by that?

    The charger was factory set to stop at 5000mah and i thought it was just picking up that my lipo battery was that capacity, As when charging a lipo it always stopped bang on 5000.
    but I noticed when charging my 3000mah NIMH it would stop and say full, and would of put in say 3801mah's.

    So then next time I charged my lipo and it stopped, i left it 15min and then charged it again and it put in another 800mah and said full for the lipo??

  6. #6
    RC Champion trax de max's Avatar
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    If your charger put 5000 into a 5000 pack, your batteries were drained really low, or your charger is overcharging.
    Google search trumps Wiki. Refer to user guide.

  7. #7
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    They are 5000mah 2s lipos and the max voltage at end of charge is 8.4v or 4.2v per cell?

    The bandit has low voltage detection set, admittedly Ive never check voltage when they have required charging??

  8. #8
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    As trax De Max says, your charger might be overcharging or you drained your batteries very low.

    I believe Traxxas default is 3.2v which is very low, so you need to check your voltage before and after charging. Either using a voltmeter or a lipo battery checker.

  9. #9
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    If it was over charging wouldnt the volts be over 8.4 volts? Is it possible it thinks its putting more in then it really is? What is the preferred method??
    I have seen on some of the battery comparo's where capacity was actually above stated capacity?? Battery type is a venom??

  10. #10
    RC Qualifier Panamon Creel's Avatar
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    Quote Originally Posted by mattryan View Post
    Also charging limit is set to 5000mah. That is what always stops the charge? Should i have it set to 5000 for a 5000mah battery or have it set higher and stops when full??
    The capacity limit of the charger is there as an added safety in case that the standard cell voltage cut off failed.
    What does your charger show when it finished charging? Does it say something like " capacity cut-off " or the normal "end charge " with the capacity it put in and the cell voltages at 4.2V?

  11. #11
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    Ive set the limit to 6000 now and the charger just switches itself off at say 5300 and says full.

    If the left to 5000 and 5000 is reached the charger just stops. Note when charging lipos they dont get even remotely warm. There is no temperature change what so ever.

    When it was set to 5000 and stopped. I once let the battery sit for 10mins then just put it on charge again and the battery stopped charging in 12 mins and added a futher 680 and said full.

  12. #12
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    Your charger, if you are NOT using a traxxas charger, should display the cell voltage at the end of the cycle.

    And, yes, it is possible to charge it to over 8.4v on a 2 cell. Though dangerous and should shorten the life of the battery. People do that so get an extra boost on races...


    I don't think lipos are supposed to be very warm after a charge

  13. #13
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    Yes cell voltage is displayed and its only ever 8.4volts. and 4.2v per cell, i've checked this.

  14. #14
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    Then you just got a 5000mah cell that is underrated. that's more runtime for free..

    Also, I'm not sure what ESC you have, but if it is adjustable, we generally suggest using 3.6v LVC. Going all the way down to 3v every time will shorten the life of your pack.

  15. #15
    RC Champion trax de max's Avatar
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    680mA seems a lot after a ten minute rest, I'm sure I done a check couple year back and managed under 30mA, maybe 17 from memory.
    It's ideal if when using packs that they're not run down to low voltage every time. Packs age quicker when stressed.
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  16. #16
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    Just ran car and checked traxxas cut out at 6.44 volts as tested on volt meter. is that ok?? or to low?
    I have another brand of vehicle that also has a lipo shut off and running a 11.1v it shut off at 9.6 volts so slightly lower again then the traxxas so Im thing it must be ok. Reading og some other forums they are saying 3.7v though thats for aircraft??
    Last edited by mattryan; 12-28-2015 at 10:04 PM.

  17. #17
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    Interesting, just finished charging again and as you can see it put in way over 5000 mah's? For the last 10 mins it was putting in 2 amps and slowly dribbled down to .4 amp before shutting down. For that whole 10 min period it was showing 8.4v and each cell was 4.2v respectively. The battery just kept taking it. I also put a volts meter on the terminals during this time and it was 8.4 volts.. As it dropped the amps to .6 and .5 it started flickering on the display 8.3v to 8.4v.
    Is it possible my battery just holds more then 5000mah's??




  18. #18
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    Quote Originally Posted by mattryan View Post
    Interesting, just finished charging again and as you can see it put in way over 5000 mah's? For the last 10 mins it was putting in 2 amps and slowly dribbled down to .4 amp before shutting down. For that whole 10 min period it was showing 8.4v and each cell was 4.2v respectively. The battery just kept taking it. I also put a volts meter on the terminals during this time and it was 8.4 volts.. As it dropped the amps to .6 and .5 it started flickering on the display 8.3v to 8.4v.
    Is it possible my battery just holds more then 5000mah's??



    It is possible it holds more than 5000mah.

    Your cut off is at 3.2v, you read a bit higher because as you use your RC, voltage would sags when you use the pack.
    As the battery pack ages, you will notice interesting things with the voltage.

    Anyways, I don't like 3.2v cut off. It's only used for extended runtime. You rarely ever let voltage drop this low when racing..

  19. #19
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    Just charged a 3s 5000mah lipo on same charger and it reckons it put in 5991 mah's for this battery as well?? I have read you can get a bit of leakage through balance charging???

    This lipo was 9.6 v prior to charging?? Finished at 12.59v was intermittent to 12.6 in the run down phase. Different brand battery too.
    Last edited by mattryan; 12-29-2015 at 12:50 AM.

  20. #20
    RC Champion trax de max's Avatar
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    It is possible to have more capacity than rated, it's only a nominal rating. But this is generally a few hundred mah, never seen nearly 1000 before. But that's charger reading.
    For a 5000 pack I still like to stick to the old 80% rule, keeps my batteries quite happy. So you should be looking at only adding 4000 to fully charge your pack after you used them.
    Google search trumps Wiki. Refer to user guide.

  21. #21
    RC Qualifier Panamon Creel's Avatar
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    Quote Originally Posted by mattryan View Post
    Interesting, just finished charging again and as you can see it put in way over 5000 mah's? For the last 10 mins it was putting in 2 amps and slowly dribbled down to .4 amp before shutting down. For that whole 10 min period it was showing 8.4v and each cell was 4.2v respectively. The battery just kept taking it. I also put a volts meter on the terminals during this time and it was 8.4 volts.. As it dropped the amps to .6 and .5 it started flickering on the display 8.3v to 8.4v.
    Is it possible my battery just holds more then 5000mah's??
    LiPo charging works in two steps, first step is CC ( Constant Current) charging where it maintains the charging amperage and voltage slowly increases as the battery takes the charge, when the voltage reaches the cut off level of 4.2V cell voltage it will switch to CV (Constant Voltage) mode. In this CV mode the Charger will try to maintain the 4.2V while lowering the amperage to achieve that until the amperage gets near 0 where it then will say its at full charge.

    Yes sometimes batteries can have a higher capacity then they indicate but usually the difference is not very high (<10%). Another reason could be that your charger has a measurement error showing higher capacity than there actually is.

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