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lipo not fully charging?

lipo not fully charging?

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Old 02-02-2014, 06:11 PM
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Default lipo not fully charging?

Hey guys, I have a gens ace 2cell 7000mah 50c battery. I just got done charging it after running it untill it stopped and My problem is that when I got done charging it, it said it only put 5900mah's into the battery. I have the hobby wing sct pro and I have read that the voltage cut off is a little low so I set it to 3.0 volts per cell before I ran it. If I set it to 2.8 volts per cell do you think that would let the battery discharge more when im running it? thanks for any help.
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Old 02-02-2014, 06:14 PM
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That's about right. You don't want to drain Lipos all the way down. You should set the cut off at at least 3.2 or higher. Your battery isn't gone last very long at 2.8v.
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Old 02-02-2014, 06:18 PM
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Originally Posted by huzzler View Post
That's about right. You don't want to drain Lipos all the way down. You should set the cut off at at least 3.2 or higher. Your battery isn't gone last very long at 2.8v.
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Old 02-02-2014, 06:38 PM
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it would let it discharge more, which is bad. if the battery is hitting 8.4 volts on the charger, but the capacity is a little lo, then you might have just gotten a bad battery.
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Old 02-02-2014, 07:05 PM
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Originally Posted by colewalker500 View Post
Hey guys, I have a gens ace 2cell 7000mah 50c battery. I just got done charging it after running it untill it stopped and My problem is that when I got done charging it, it said it only put 5900mah's into the battery. I have the hobby wing sct pro and I have read that the voltage cut off is a little low so I set it to 3.0 volts per cell before I ran it. If I set it to 2.8 volts per cell do you think that would let the battery discharge more when im running it? thanks for any help.
1. Some Chargers have a time or Mah cutoff, check and make sure this is not the case. Some chargers have a default charge cutoff at 5000 or 6000 Mah.

2. Running you pack down to about 5900 is about right out of a 7000mah pack. I have a 6900 and when I hit the 3.0 cutoff in my SCT truck I put about 5500 - 5600 back into the pack.

Good Luck!

Alan
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Old 02-02-2014, 07:18 PM
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What is your end voltage when it does cutoff?

In addition to what others have said, try setting the cutoff to 2.8 a cell. The LVC on the hw and many others seems to be off or inaccurate. I have mine at 2.8 a cell and it cuts off at 6.3v on a 2s pack or roughly 3.1v per cell. I have had 4 or so of these esc's and all have been the same. Very rarely do I run a pack to cutoff but if I do in practice, this is what I have always found. Hope this helps
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Old 02-02-2014, 07:49 PM
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to the op. discharge it on the charger to 3.0 or 3.2 volts per cell. then charge it back up. you can see the full capacity of the battery.
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Old 02-02-2014, 07:49 PM
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Originally Posted by ovalracer1m View Post
What is your end voltage when it does cutoff?

In addition to what others have said, try setting the cutoff to 2.8 a cell. The LVC on the hw and many others seems to be off or inaccurate. I have mine at 2.8 a cell and it cuts off at 6.3v on a 2s pack or roughly 3.1v per cell. I have had 4 or so of these esc's and all have been the same. Very rarely do I run a pack to cutoff but if I do in practice, this is what I have always found. Hope this helps

Please dont set your cut off to 2.8v a cell dropping a lipo under 3.0v a cell can damage them and in some cases start fires.
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Old 02-02-2014, 07:50 PM
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Originally Posted by smokinu View Post
Please dont set your cut off to 2.8v a cell dropping a lipo under 3.0v a cell can damage them and in some cases start fires.
they were doing it only because of the faulty cutoff.
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Old 02-02-2014, 07:53 PM
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Originally Posted by ThePanda View Post
they were doing it only because of the faulty cutoff.
Dosnt matter. What if the lvc dosnt cut off early and he drains his pack below 6.0volts. Its not good for anything

You are risking a lipo going under voltage for what 1 extra lap...
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Old 02-02-2014, 08:45 PM
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Keep in mind when LVC hits, thats under load. If you had a data logger you'd see the voltage drop that low, hit LVC, that if you leave it all on you'll see the voltage go back up. Discharging it to 6v on your charger then fully charging it will give you an idea with what capacity its actually taking, but if the cells aren't matched it might throw your pack way out of balance so its best to just check the voltage after a run, if its showing just under 7v that capacity sounds right and a safe way to run the pack.
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Old 02-02-2014, 09:53 PM
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isn't lvc only triggered if it remains at the cutoff for more that the set time (a second or two)? this so it doesn't get triggered early by voltage drop?
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Old 02-02-2014, 09:56 PM
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as soon as it hits the voltage, it then takes a couple seconds and the voltage will rise, but its not recommended to keep driving at that point
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Old 02-03-2014, 12:46 AM
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Originally Posted by smokinu View Post
Please dont set your cut off to 2.8v a cell dropping a lipo under 3.0v a cell can damage them and in some cases start fires.
The OP asked for a answer to a possible early cutoff. I gave an answer to known LVC inaccuracies. It's not a case of it cutting off at one voltage them all of a sudden another. Just inaccurate on the way safe side.
I agree with you, but if you seen where I said "the LVC may not be accurate, so you may have to set it at 2.8 to get a 3.1 cutoff". Didn't say It was a right decision for all, just what I find I and many others do to get a accurate cutoff. May have to test your exact application to see where you have to be.

Last edited by ovalracer1m; 02-03-2014 at 12:57 AM.
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Old 02-03-2014, 09:22 PM
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Default issues with battery

ok so i just got done running my battery down with the LVC set to 3.2 and after charging it, it said it only put 4700mah in the battery. any help with this one? should I set the lvc to 2.8 and see what happens? or should i stick with the 3.0 LVC?
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