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  1. #1
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    LiPo batteries and Unbalanced volts

    as the title says, every ODD once and a while when i throw my batteries on the charger (i always balance charge) it says there is an unbalanced volt and waits for that to clear up before letting me charge.

    the last 4 or 5 times i went out i havent received that message when charging.

    what does unbalanced volts mean? are they bad? am i running the batteries too far down? (have lipo cutoff on 3.4V)

    when i had a mini savage i had to balance the darn thing EVERY time i charged it!!

  2. #2
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    Too low of Discharge C rate lipo could be struggling with demand?

    Poor lipo to charger connection giving false readings?

    Did not unplug lipos from the truck overnight?

    Conclusion: Needs a $4 ebay cell voltage checker.

  3. #3
    RC Turnbuckle Jr.
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    Out of balance so far the charger is mad?

    Are you getting any cell readings, what are we talkin here?

  4. #4
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    i think i have most of those bases covered, i shut my truck off by unplugging BOTH batteries, though even one should be ok, right? *opens the circuit?
    the batteries and chargers all have freshly soldiered plugs on them too, i used those EFlight bullet style ones. -and i over soldier and have to fight to get them in the plastic. haha
    the batteries are 35C, is that not high enough?

    OOOOR are Venom brand batteries not the greatest? but like i was also saying, last handfull of runs i had no problems on the charger.

  5. #5
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    theyre not bad, it will be like 0.017 of a volt or so. ive never seen it hit 0.02x anyway.

  6. #6
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    can i check cell readings with a multi meter and the balancer plug? im also not using an extension. i have the lipo 3" away from my charger. lol

  7. #7
    RC Turnbuckle Jr.
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    2 hundreths of a volt difference gets an error out of your charger?

    I say you're all good dude.

  8. #8
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    yeah my Passport ultra always seemed a little fussy about it. i always let it balance it though.

  9. #9
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    oooh nuts, maybe i was wrong, 176mV is the picture on my cellphone. the battery thats on there now charging is unbalanced for 7mV -but its charging. lol

  10. #10
    RC Turnbuckle Jr.
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    My older packs are starting to wander a bit, they'll be off .2 volts by the end. But as long as we're staying in the safe zone, I think its fine. They charge up balanced, but come out after running a bit off.

  11. #11
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    if i were to take them right out of the truck after running them down to the cut off and charge them within minutes, would that not help the unbalanced volt? ive done that a few times before

  12. #12
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    What is your lnc set for and are you running the packs down until they hit the lvc?

  13. #13
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    Quote Originally Posted by bentrocker View Post
    What is your lnc set for and are you running the packs down until they hit the lvc?
    whats an lnc set?
    and i run em till my friend i usually go out with breaks his truck or runs out of nitro.... he didnt think this was going to be this fast when i told him i got two 3s packs either! haha
    Last edited by ClintOnNitro; 03-12-2012 at 01:09 PM.

  14. #14
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    You could half charge them to storage mode right after running. Looks like they are drifting out while resting after a run. 35c is good. Yeah you can read with volt meter. You can read pack total across red and black or read the individual cells by reading across it's two leads. Be careful not to short out your meter leads stabbing at the balance tab.

  15. #15
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    The lvc is low voltage cutoff. With programming that can be 3.0v -3.5v under load per cell. The bad thing about lipo LVC is that it takes the total voltage and divides by the number of cells you have. So a 4s setup could be set to end at 3.0v lvc but actually read 2.90,2.90,3.10,3.10. Thats why a little higher lvc (3.2-3.5) can keep all of your batteries running for a long time.
    Its All relative to your perspective.

  16. #16
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    LVC is set to 3.4, but is 150mV unbalanced really that bad?

  17. #17
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    I find when I run my truck till I hit the LVC my lipos tend to be a little out. But if I only run down to around 3.7 or 3.8 they are fine.

  18. #18
    Marshal Dadx2mj's Avatar
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    This question should be addressed to Venom since they are the manufacture of the battery in question. Traxxas does not allow this type of product support for other companies products.
    BlindMan Racing
    Rusty - MERV - Pede 4x4-Alias
    SPC Lipo Power

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