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  1. #1
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    No One Balances Their Lipos

    I was at the race track today and I brought all my gear with me. Which isn't really all that much... but any way... as is typical me, I forgot to bring something --- the taps connector cord for my 2S lipo. I noticed after I was done with the pre-race practicing. I talked to 3 different people there that run electrics to see if I could find/borrow a balancer cord. All three of them use lipo.

    None of them balance when they charge. I was pretty amazed. One guy said he balances his packs so infrequently that guessing once every six months was a decent guess.

    They all looked at me like some sort of freak. One guy said that he only does it when he starts to notice the pack behaving weird. I replied, "Well if it starts behaving weird, it's kind of too late because they're so far out of balance one might be below or over voltage." He goes, "Nah just plug it back in and it'll take care of itself."

    Needless to say, I didn't charge without my balancer. I ended up not racing.
    I'd rather take care of my pack and get the best possible performance from it. I don't care how good those guys drive.
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  2. #2
    Traxxas Marshal cooleocool's Avatar
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    Some people need to do a little more research! I ran into the same thing with someone I met not long ago. He had a few li-po packs, so he got those out to show me. He he pulled one out and started squeezing it a little bit (it looked puffed to me) and he said something to the effect that he should probably balance that pack. . .

    I'm with you on this one... I don't currently have any Li-Po packs, but I sure as heck will buy a proper balancer and will be balancing them frequently.
    "Happiness depends upon ourselves." -Aristotle

  3. #3
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    sounds like playin` baseball with a grenade. I know a guy that burned his van to the ground with lipo`s. Good choice IMO.
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  4. #4
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    I don't get why you wouldn't just do it for longevity and performance sake??

    Its not like there is any difference between plugging in one plug versus two.

  5. #5
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    The one fellow that I quoted above said that it's 10 minutes faster to charge without the balancer.

    <sigh> I bet he has multiple packs, too. I just don't get it.
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  6. #6
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    Some hard case lipos don't come with a balancer connector.
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  7. #7
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    Quote Originally Posted by NEVADAGARY
    Some hard case lipos don't come with a balancer connector.
    Really? Which ones?

    I find that hard to believe.
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  8. #8
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    some dont look like they have balance connectors, but you will usually see a small hole in the case for a third wire... the balancer hooks up there....


    Some of the very first hard case lipos did not have any way to balance tho.... The guys who do not balance obviously dont have a good enough charger to see that its really very easy and not any slower... in all actuality if you balance you can safetly charge a little over 1C and get them done faster.... some flightpower batteries are rated at 2C charging with a balancer....

  9. #9
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    Well.. nah.. they have good chargers. It can't be blamed on their equipment. One guy had a really nice Hyperion charger... I saw another with a Triton.

    They're just retarded. That's pretty much all there is to it.
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  10. #10
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    NO BALANCE BATTERIES HOUSE GO BOOM! lol
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  11. #11
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    Racers usually push everything past the limit or "longevity." I am thinking you can charge much quicker without a balancer because all cells are charging at once. When the charger see maxx voltage it stops. I don't know if the will actually give you best performance because one cell might be low and your total voltage won't be as high. Higher charge rate with out a balancer is why the racers probably don't balance.

  12. #12
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    i balance every single time i charge my lipos. even if i am just topping off the pack.
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  13. #13
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    FWIW, Larry from Kokam America told me that balancing their 2S Li-po packs was optional, where as balancing the 3S and larger was mandatory. This was for Kokam packs and the packs they manufacture for Orion/Peak. He said that he could not speak for lesser quality Li-po. In their extensive testing after hundereds of cycles, he said the 2S time and time again showed no need for balancing if they were charged and discharged properly. This was as of a little over 1 year ago.

  14. #14
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    Quote Originally Posted by rampit
    ...he said the 2S time and time again showed no need for balancing if they were charged and discharged properly.
    Okay. So if I run my lipo in one vehicle, it's discharging. If I run it in another vehicle, it's still also discharging. When they both have a cut-off set appropriately, who/what's to say what is "properly discharged?" That doesn't make any sense to me.

    Sure I know you aren't the answer man, just the messenger, I'm just showing that "discharged properly" is a load of crap.

    Even "charging properly"... I don't understand that either. A Hyperion charger will charge just the same as a Triton charger without a balancer. Both chargers will see the pack as one big cell and dump electricity into it until it reaches max voltage. That sounds proper to me.

    Hogwash. Plain. And. Simple.

    Cells will discharge differently either because of imperfections in the cell (not pack) manufacturing process or because of age of the pack. It is up to a balancer to be able to see each cell individually too keep the higher voltage cell from over charging.
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  15. #15
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    I am thinking 2s2p lipos is what he is saying won't need balanced(most all 2s lipos). With only having 2 cells it should balance it's self out because there is no way for one cell to get too far out of voltage since they are being drawn equally from. While a 3s lipo has three different sources and thus can more easily get out of balance.

  16. #16
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    Under normal circumstance chargeing the pack will bring the cells back to perfect balance without a balancer. It is unfortunate that many manufacturers , vendors, users do not understand balancing series wired cells that those who advocate "insisting upon using a balancer" every charge know very little of what is going on with the specific pack during the balancing procces. Many of those who advocate "never balancing" know far more of what goers on in the pack when charged/discharged. There are others , however who claim "never need balancing" who are just in the dark as to what the pack requires.

    It is not a complicated subject at all and a dvm and a non-balancing charger would explain a lot about "cell balance"
    4s Pede, 6S Maxx, 3S Rusty, 6S slash

  17. #17
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    Having used lipo batts for rc aircraft for about 5 years , and none of the 2 cell or 3 cell lipos had any thing other than just the 2 wires , .
    Out of the 14 lipos that I used in my rc planes , many , many times recharged , ONE of my 3 cell 2100 mah lipos , this spring , must have opened up inside , because it is just a open circuit , no voltage , nothing .
    So I do not belive that lipos have to be balanced every time , if at all .

    Although I have now purchased a lipo balancer , and sometimes use it on the new hard case rc truck lipos that I am useing now , because they have the additional wires for it .

    Do not try this at your home !

  18. #18
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    Quote Originally Posted by 4.5emaxx
    With only having 2 cells it should balance it's self out because there is no way for one cell to get too far out of voltage since they are being drawn equally from. While a 3s lipo has three different sources and thus can more easily get out of balance.
    Sources? What? Being 2 cells or 3 cells they are all being drawn upon. The source is still the motor... so there isn't more than once source.
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  19. #19
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    I don't know what on earth the difference is.
    But let me tell you.. I use lipo also. I have for almost 2 years now. Every single one of my lithium packs, even my 1/18th packs benefit from balance charging. How do I know? Because I look at the cell voltages when I plug in the pack to charge.

    I'm not on PCP. I'm not a salesman for balancing equipment. But I know what I see in all the lipo packs I have ever used. To assume that cells in series will self balance is ridiculous -- just ask all those people that even have NiMH cells blow up. It's because they were not in a matched pack and the cells were uneven. They did not "self-balance" over time. I'm sorry but it simply won't happen. The cells in parallel will because of the nature of electronics and constant voltage vs. amperage.

    To think that your lithium packs don't need to be balanced is just naive. It will lead to an eventual premature pack death. Any one in this situation will just attribute it to "the way it goes" from not knowing any better. If the pack was maintained, it would have had much more longevity.
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  20. #20
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    Being in balance and self balancing might be two different things. A normal pack will self-balance in a sense that equal capacity will be drawn out and replaced. A pack will never self balance in the same sense that a nimh pack will when trickle charged. Lipos are stupidly predictable.

    Also being in balance and balancing and using a balancer are very different things.

    Most of my packs are in perfect balance without using a balancer. If they are out of balance then they get balanced.

    Packs should be in balance at every charge , yet may never need to be actively balanced. If they are found to need it, by all means bring them to equal voltage at the top.
    4s Pede, 6S Maxx, 3S Rusty, 6S slash

  21. #21
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    Quote Originally Posted by rupert
    If they are found to need it, by all means bring them to equal voltage at the top.
    And as I told that racer guy, how will you know when one is to need it? When it starts behaving badly? When it puffs? I cannot think of one good example of a pack needing maintenance before damage, but I can think of several that show a pack has already been damaged that maintenance will not fix.
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  22. #22
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    Quote Originally Posted by 69Malibu
    i balance every single time i charge my lipos. even if i am just topping off the pack.
    Darn right. If you don't you are asking for a very hot fire hazard.

  23. #23
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    Quote Originally Posted by Slasher
    And as I told that racer guy, how will you know when one is to need it? When it starts behaving badly? When it puffs? I cannot think of one good example of a pack needing maintenance before damage, but I can think of several that show a pack has already been damaged that maintenance will not fix.
    No, by that time it is too late. The pack can/will be damaged long before one can tell by using it. Simply check the cells when charged.

    Something that may clear up some of the mystery is this:

    When dischargeing or chargeing series connected cells the capacity added or subtracted from all cells in the pack will be equal. Even if the IR is grossly different and the total capacity is grossly different and the voltage under load (or charge) is grossly different. The cells are very predictable.
    Last edited by rupert; 09-07-2008 at 06:23 PM.
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  24. #24
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    There is an easy way to tell if you packs need to be balanced all the time or not, check the individual cell voltage when your done running them. If your cells are out of balance then you need to balance them. (seems obvious right)

    The primary causes of cells not discharging evenly are cheap cells, inferior pack construction (including using cells of differing internal resistance), factory defective or weak cells, discharging below the minimum safe voltage, and over heating (usually from too small pack or too small "C" rating for application) the cells.

    Properly selected quality packs should not discharge unevenly. If they do there is a problem and is most likely the first indication that your pack has a problem that you should be paying attention to. So if you are not balancing every time you charge you should at least be checking the individual cell voltage to make sure that your pack is not developing a problem.
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  25. #25
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    A check at the discharged state is the source of some of the misinformation regarding imbalance. If the pack started out balanced and was discharged as a pack in a relatively timely fashion (within a month) then the cells would be balanced when recharged withouit a balancer.

    If this is not the case then there's some real trouble with the cell(s).
    4s Pede, 6S Maxx, 3S Rusty, 6S slash

  26. #26
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    Quote Originally Posted by Slasher
    Okay. So if I run my lipo in one vehicle, it's discharging. If I run it in another vehicle, it's still also discharging. When they both have a cut-off set appropriately, who/what's to say what is "properly discharged?" That doesn't make any sense to me.

    Sure I know you aren't the answer man, just the messenger, I'm just showing that "discharged properly" is a load of crap.

    Even "charging properly"... I don't understand that either. A Hyperion charger will charge just the same as a Triton charger without a balancer. Both chargers will see the pack as one big cell and dump electricity into it until it reaches max voltage. That sounds proper to me.

    Hogwash. Plain. And. Simple.

    Cells will discharge differently either because of imperfections in the cell (not pack) manufacturing process or because of age of the pack. It is up to a balancer to be able to see each cell individually too keep the higher voltage cell from over charging.

    Slasher, I wasn't trying to discredit or undermind anything you were talking about. Sorry if it came across that way. Since we were discussing balancing I just thought I'd throw that little "FWIW" out there incase it was useful to someone. As I said, he made no claims of the effects of balancing or not balancing on any packs other then the ones his company (Kokam) produced for themselves and for Orion/Peak. I do know that Larry has been using Lipo batteries for as long as the technology has been around both in his work, and his hobby RC airplanes. From the smallest packs, to the largest. Way before anyone even thought of putting Lipo in a land vehicle. In other words he didn't just fall off the RC turnip truck. Through my own use with those packs, I found what he said to be true. After a couple hundered cycles without balancing, I balanced them and I can't remember the exact number, but they were within factory spec as being still matched. They had done some really extensive testing far beyond what I did with the same results. He did make clear he would not trust not balancing to anything outside of 2S kokam and the orion/Peak equivalents. I wish the conversations would have been more recent so my feeble brain could remember more.

    You can't go wrong balancing, that's a fact. He was just trying at the time to prove to me that with the quality of their cells it was not necessary unless you were into the 3S and 4S versions of those packs. I did want to do a better job clarifying though that this was just a story I wanted to share and this is not something you want to try with Maxamps and the like, or you might get a different result.

    Also to further clarify my original post, I think what he meant by as long as they were "charged and discharged properly" was that if I ever accidently overdischarged them in the car, or managed to overcharge them by setting up the charger wrong they would then need to be balanced for sure (if they were even still safe to use). Atleast that's what I remember from it..

    I don't have the answer, just wanted to share what I thout was a story related to the topic we were discussing.

    Peace
    Last edited by rampit; 09-08-2008 at 12:56 AM.

  27. #27
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    http://forums.radiocontrolzone.com/showthread.php?t=235232&page=2&pp=25.
    Pay attention to posts by Shawn Palmer, once known as "Mr. Mamba" but no longer affiliated with Castle Creations. Very interesting reading. I still balance my LiPos every time I charge them ANYWAY.
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  28. #28
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    Ok, I think we need to know why packs go "out of balance". Out of balance means that one cells voltage (2s pack for example) is different from another. What is the most common way a pack can get out of balance?? Heat is the answer. As a cell heats up, its resistance changes. As its resistance changes, so does its discharge rate.

    So... your 2s pack is in your vehicle... the bottom cell does not have the same ventilation as the top cell.... if you run to the point of heating up the pack, the bottom cell gets hotter than the top cell and the pack slowly but surely goes out of balance... a miliamp or ten at a time. Now for the next part.

    When you charge a lithium pack, the charge has two phases, a constant current (CC) stage and a constant voltage (CV) stage. the CC stage is the first part and is where the charger outputs the amperage you select to the battery. It does this until it sees the packs peak voltage (on a 2s pack it is 8.4v, 4.2 volts per cell) when it hits its peak voltage it goes to the CV stage and finishes off the pack.

    We are interested in where each cell is at when it hits its peak voltage. If one cell is out of balance, one cell will be overcharged, and one cell will be undercharged when that peak voltage is hit. If one cell is at 4 volts, and the other is at 4.4 volts, the charger will hit the second stage and overcharge the 4.4 volt cell. It also undercharges the other cell, and the next time it is discharged it can go below the low voltage point which damages the cell.

    This is not terrible for a few charges, but over time it becomes dangerous as well as ruining the packs life. Also, as a cell gets damaged, its C rating decreases, which usually causes more heat buildup in a pack... its a vicious cycle scenario...

    Now, why do some people not have as many issues as others. Could be because they don't have heat issues because of good C ratings or good ventilation.....

    Ok, so what have we learned??.... Heat is bad, charging a warm pack is bad, not balancing a pack that heats up when used is BAD... moral.... balance or take away heat, or other sources of resistance in batteries...

  29. #29
    Traxxas Marshal cooleocool's Avatar
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    I just read something on balancing last night, and they claim that balancing is a gimmick. If you're interested, have a read:

    http://www.pfmdistribution.com/

    It's towards the bottom of the page.
    "Happiness depends upon ourselves." -Aristotle

  30. #30
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    Cells in series will always be discharged at the same rate regardless of IR or temp or voltage. Same with chargeing , even a 4 volt cell series connected with a 1.5 volt cell will have the exact same current since it is a complete circuit. Heat or cool them and the whole circuit gets the same current.

    Normally cells go out of balance because of varying self discharge rates or being damaged by overuse/abuse.
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  31. #31
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    I will do what the fine folks at Maxamps say and that is balance while charging. Best for the batteries and safest way to charge them as well. Some people can claim what ever they want but at $155 per battery and the thought of burning down my home I will handle lipo's the way the experts say you should.

  32. #32
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    Quote Originally Posted by cooleocool
    I just read something on balancing last night, and they claim that balancing is a gimmick. If you're interested, have a read:

    http://www.pfmdistribution.com/

    It's towards the bottom of the page.
    It's true. Qaulity matched packs rarely need balancing when used within it's limits. Lower qaulity battery packs get out of balance pretty quick. Especially when you draw lots of current out of them.

    The nice thing with A123's, is that you can overcharge them a bit and it will balance itself out when the pack self discharges.
    Last edited by snellemin; 09-09-2008 at 05:32 PM.
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  33. #33
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    Wow! So if I understand that article right, I should stop using my Hyperion built-in balancer, and, if I "insist on the balancing gimmick", should get something like a Blinky and balance after the pack is fully charged. Am I understaing it correctly?
    DTM rocks! Audi kicking some M-B rear! :)

  34. #34
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    All I use is a blinky to discharge my packs a bit faster when I overcharge them to balance out(this is so I don't blow my MM ESC's when I plug them in).
    I recommend balancing your packs if you are not familiar with their characteristics or if you bought cheap packs.
    Last edited by snellemin; 09-09-2008 at 05:41 PM.
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  35. #35
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    RRRright. I have enerland cells, and they need balancing. So there goes that theory.

    Its like driving with no seatbelt, sure you can do it for a while, but sooner or later....

    Why risk burning a house down over a $30 balancer?

  36. #36
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    Quote Originally Posted by snellemin
    All I use is a blinky to discharge my packs a bit faster when I overcharge them to balance out(this is so I don't blow my MM ESC's when I plug them in).
    I recommend balancing your packs if you are not familiar with their characteristics or if you bought cheap packs.
    I always balance my packs when I'm charging them with the Hyperion EOS0606i. The lipo I use most frequently is a hard-cased SMC 2S 5000 28C. The others are Maxamps lipos. Mabye I missed the answer, but should I stop using the Hyperion balancer, and start using a Blinky after charging?
    DTM rocks! Audi kicking some M-B rear! :)

  37. #37
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    Quote Originally Posted by jdjdtdmd
    Mabye I missed the answer, but should I stop using the Hyperion balancer, and start using a Blinky after charging?
    I think that if what you're doing works, don't change anything.
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  38. #38
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    Quote Originally Posted by outkast187
    ...

    Why risk burning a house down over a $30 balancer?
    But they also claim that there have been no reported fires when using "their" chemistry (I would assume they are talking about Li-Mn).
    "Happiness depends upon ourselves." -Aristotle

  39. #39
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    Quote Originally Posted by cooleocool
    I just read something on balancing last night, and they claim that balancing is a gimmick. If you're interested, have a read:

    http://www.pfmdistribution.com/

    It's towards the bottom of the page.

    The one thing that stuck out to me on that page was the sentence that read "properly matched packs". With most of the vendors being money hungrey we may never really see nicely matched packs. Perhaps this is why they suggest we balance them.
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  40. #40
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    I doubt that blancing the pack every time you charge is necessary. If it needs that, it is probably toast anyway. I haven't had a problem using a balancer while charging.

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