# lipo balancing



## Porksalot4L (Nov 4, 2002)

i have a 3200 smc lipo and ran it a few times. how often should i balance it? i havent yet because i dont own one yet. will it kill the battery not to use one? how often should it be used?


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## OvalmanPA (Mar 21, 2000)

Will it kill it? Well over time just like a NiMH the cells can get to be different voltages so one cell can be over charged/discharged which in turn could prematurely kill the pack. You might want to have a look at the SMC lipo thread in the oval product support area as I think Danny had a recommendation on how often to do any balance charging. Some companies recommend to do it every time. Others every so many charges. I have a Reedy pack and a Equinox balancer. I figure I have the balancer so why not use it every time?


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## trailranger (Feb 9, 2006)

Some of the newer chargers have built in balancers. If the pack is out-of-whack on cell voltages it will not start charing untill the voltages are closer. Then while it charges will balance the cells saving the time of having to balance before the chrage.

On my Hyperion 610i I only had the wait a few times before the charge started becuase of the cells having way different voltages. The extra wait was only a few minutes before the charger ramped up the amperage to full but I am sure it most likely saved one of the cells from being overcharged.


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## smoothie (Mar 23, 2004)

I have learned a bunch about lipo's over the past 6 months due to flying them in all of my helicopters. The big no no is to not run it past 80% meaning you should never have to charge more than 80% of it full capacity. Another thing to keep in mind is to keep them at room temps. With winter fast approaching for many of us, lipo's cannot handle extreme temp changes and the cold will damage to battery and shorten the amount of cycles you will get. Many chargers have balancer included with them. I balance all of my lipo's every time I use them. The two chargers I really like are made by thunder power. The Thunder Power 610 is a nice charger for someone on a budget. It includes a balancer. The Thunder Power 1010 charger is much nicer and capable of charge higher amounts of cells. There is no balancer included. I recommend the thunder power 210 balancer. The 1010/210 combo is one of the best on the market at this time. I hope this helps.


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## TomHargrave (Oct 13, 2007)

smoothie said:


> I have learned a bunch about lipo's over the past 6 months due to flying them in all of my helicopters. The big no no is to not run it past 80% meaning you should never have to charge more than 80% of it full capacity. Another thing to keep in mind is to keep them at room temps. With winter fast approaching for many of us, lipo's cannot handle extreme temp changes and the cold will damage to battery and shorten the amount of cycles you will get. Many chargers have balancer included with them. I balance all of my lipo's every time I use them. The two chargers I really like are made by thunder power. The Thunder Power 610 is a nice charger for someone on a budget. It includes a balancer. The Thunder Power 1010 charger is much nicer and capable of charge higher amounts of cells. There is no balancer included. I recommend the thunder power 210 balancer. The 1010/210 combo is one of the best on the market at this time. I hope this helps.



Good info smoothie.

So is 8.44 volts for the standard 2s or whatever LiPo packs 80% charged? So when people talk about "over charging" they really mean charging more than 80%? (seems like the percentage is just a number pulled out of the sky so to say....I understand it could be more or less, probably more I would guess).

You say extreme temperature changes damage the battery and shorten the amount of cycles you will get. I'm curious how long a LiPo will stay at it's peak-performace when it is treated correctly. Correctly could be subjective I imagine as I'm not sure if the way racers treat them is correctly or not??

just trying to learn


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## Racin'Jason 8 (Nov 19, 2002)

Tom,

A typical Lipo cell has a nominal voltage of 3.7V...so a 2s (2 cells in series) Lipo would have a nominal voltage of 7.4V in theory, but as you know with our 2S receiver packs they charge to 8.4. The 8.44V rule is used as a line in the sand to deter overcharging. 

What smoothie means about his 80% statement is this...the packs shouldn't be discharged past the 20% capacity point. If you have to recharge the pack with more than 80% of it's rated capacity, then you used too much. If you have a Lipo cutoff on whatever you are using then it doesn't matter.

Hope that makes sense.


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## swtour (Oct 8, 2001)

For OVAL Racing we're using 1500 to 1800 mAh on average with 21.5 motors, and closer to 2000 - 2400 in 17.5 

This is for 5 minute racing.

We're using 3200 mAh - so that would mean we're using 75% of the rated 3200 mAhs

The LIPO batteries (ORION) performed for the most part FLAWLESSLY for a Year running them almost every weekend this past 14-15 months.

The EXTREME cold weather IS something that I've read will KILL a LIPO deader than a doornail. (So - careful how and where you store them, and never (from what I read) use them if they are TOO cold ....warm them up )

We don't generally have to deal with that on the west coast!


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## ta_man (Apr 10, 2005)

Racin'Jason 8 said:


> What smoothie means about his 80% statement is this...the packs shouldn't be discharged past the 20% capacity point. If you have to recharge the pack with more than 80% of it's rated capacity, then you used too much. If you have a Lipo cutoff on whatever you are using then it doesn't matter.


It still matters.

Unless you have a cutoff voltage you can adjust, you will end up discharging them way more than 80% if you run to the cutoff. The typical LiPo cutoff on ESCs that have a fixed cutoff is 6.0 to 6.25V.

The fixed cutoff in Novak ESCs designed for 2S LiPos is 6.25. If you run it this low, you are going to end up with it 95% to "100%" discharged. That is too much to get the best life out of your packs (not that everyone cares about that). But it is only really an issue when practicing with no time limit. Most races aren't long enough to dump a pack and reach the cutoff (unless you are running Mod).

Also, if you check the pack after you are don and see that it still reads 7.0V you may think you have a lot left in it. That is not the case. Just like a near empty NiMH that reads 1.2V a fully (but safely) discharged LiPo will still read 7.0V. This was a table I found in another HobbyTalk post:

An open (resting) voltage is a good indicator of state of discharge.

4.2 at the top and 3.5-3.7 at the bottom depending upon who you talk to.

-%- -1s- -2s- -3s-
100 4.20 8.40 12.60
90. 4.13 8.26 12.39
80. 4.06 8.12 12.18
70. 3.99 7.98 11.97
60. 3.92 7.84 11.76
50. 3.85 7.70 11.55
40. 3.78 7.56 11.34
30. 3.71 7.42 11.13
20. 3.64 7.28 10.92
10. 3.57 7.14 10.71
0.0 3.50 7.00 10.50


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## Lazer Guy (Sep 12, 2005)

TomHargrave said:


> Good info smoothie.
> 
> You say extreme temperature changes damage the battery and shorten the amount of cycles you will get. I'm curious how long a LiPo will stay at it's peak-performace when it is treated correctly. Correctly could be subjective I imagine as I'm not sure if the way racers treat them is correctly or not??
> 
> just trying to learn


I have also been concerned about the temp of lipo's especially in the winter.
Like everything you ask 10 people you get 10 different answers.
I contacted the manufacture of my lipo's and this is what I was told.

You should pre heat them for 2 hours to between 70* and 80* before charging them and keep them at that temp for the whole race day. 
This will make them last as long as they possibly can. Store them with 50% to 75% in them, check them weekly for Volts and keep them at lest 50%. 

I test my lipos every 4 weeks for IR at room temp. I feel with any battery the IR will tell me if they are any good or not and how they are doing.


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## onefastdude (Nov 6, 2002)

smoothie said:


> I have learned a bunch about lipo's over the past 6 months due to flying them in all of my helicopters. The big no no is to not run it past 80% meaning you should never have to charge more than 80% of it full capacity. Another thing to keep in mind is to keep them at room temps. With winter fast approaching for many of us, lipo's cannot handle extreme temp changes and the cold will damage to battery and shorten the amount of cycles you will get. Many chargers have balancer included with them. I balance all of my lipo's every time I use them. The two chargers I really like are made by thunder power. The Thunder Power 610 is a nice charger for someone on a budget. It includes a balancer. The Thunder Power 1010 charger is much nicer and capable of charge higher amounts of cells. There is no balancer included. I recommend the thunder power 210 balancer. The 1010/210 combo is one of the best on the market at this time. I hope this helps.


What would be the big benefit of the 1010 vs 610? I read the features and really don't see much difference besides price!


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## B.A. Sanders (Apr 6, 2004)

*Need opinions*

Above I see a choice or two on chargers. I've been racing for 5 years.
Very shortly at dirt oval and onroad 1/10 electric. Run a xxxt and tc3 is all.
Most of those years have been racing 1/10,1/8 nitro offroad. So I'm not that
good of an electric racer. Always used a Pit Bull charger on my six cell nimh.
Now my boy is 5 and has started going with me. He's gonna run the Slash
class and 1/10 scale elec. truck. So I'm in the market for a GOOD charger that will do all batteries, balance, cycle, etc...
Any suggestions????

Brent


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## ta_man (Apr 10, 2005)

B.A. Sanders said:


> Above I see a choice or two on chargers. I've been racing for 5 years.
> Very shortly at dirt oval and onroad 1/10 electric. Run a xxxt and tc3 is all.
> Most of those years have been racing 1/10,1/8 nitro offroad. So I'm not that
> good of an electric racer. Always used a Pit Bull charger on my six cell nimh.
> ...


My suggestion would be an ICE or a Checkpoint with a separate balancer. For LiPo I think the Hyperion changes with the built-in balancers are great but having charged one NiMH pack with mine I won't do it again. The miniumum peak detect value was 3mv/cell and that was too much - the pack got way overheated.


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## CClay1282 (Jan 5, 2006)

if 3mv per cell overheated you pack that much there has to be something else causing it. I charged nimhs on my ice and that is as low as it goes and no problems.


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## B.A. Sanders (Apr 6, 2004)

Thanks TA MAN. The ICE was one of my picks, but I noticed it didn't have a built in
balancer. I didn't give a thought about an independant one. Do you have to balance 
Lipos each time you charge them? I know nothing about Lipos. But prob gonna have to get into it.


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## ta_man (Apr 10, 2005)

CClay1282 said:


> if 3mv per cell overheated you pack that much there has to be something else causing it. I charged nimhs on my ice and that is as low as it goes and no problems.


I've charged packs on my ICE too without getting them overheated. Maybe the Hyperion isn't quite as sensitive as other chargers in NiMH mode. Whatever the reason, I got the Hyperion mainly for its LiPo capabiluties and that's all I'm going to use it for now. For LiPo it is awesome.


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## ta_man (Apr 10, 2005)

B.A. Sanders said:


> Thanks TA MAN. The ICE was one of my picks, but I noticed it didn't have a built in
> balancer. I didn't give a thought about an independant one. Do you have to balance
> Lipos each time you charge them? I know nothing about Lipos. But prob gonna have to get into it.


Since I mostly use the Hyperion with the built-in balancer for my LiPos, there's no reason for me not to balance them every time. I know for sure the Hyperion charges my SMCs faster that the ICE with a separate balancer. I think the Hyperion also charges the LiPos faster when the balancer is connected. Since the charge current isn't going through the balancer on the Hyperion, it stays in constant current mode longer.


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## B.A. Sanders (Apr 6, 2004)

Thanks man, appreciate the help.:thumbsup:


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## Slider (Dec 7, 2003)

B.A Sanders Ck P.M


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## B.A. Sanders (Apr 6, 2004)

Back at ya SLIDER!!!!!


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## rjvk (Aug 27, 2003)

I sort of wonder about cold hurting the packs. Obviously , trying to charge a cold pack is bad, but how can letting the pack get cold be so detrimental? Remember, the pack is definitely going to get very cold in the overseas container, and the UPS trucks on the way to the hobby shop...


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