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Old Nov 10, 2011, 01:41 PM
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I just put it on at 10.8 volts, .5 amps on the nimh setting. I let it stay on for about 15 minutes until the charge was reading over 10 volts. Took it off and plugged the voltmeter in and it lit up! It read about 3.4 volts for each cell. So then I put it to charge normally as a lipo and I'm just waiting to see how it turns out. Its charging at 2.2 amps, maybe I should have reduced that a bit.
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Old Nov 10, 2011, 02:02 PM
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I've been checking on it and it appears cell #2 is low. It's been at around 3.83 while the other 2 cells are at 4.25

The funny thing about this is I never overdischarged this battery. It just went dead like this. I unplugged it right after my last flight and left it overnight. The next day it was dead. Strange.

I guess if the other cell doesn't catch up I'm going to just toss it?

Edit Update: It spent 75 minutes on the charger and that cell never got up past 3.91 The others stopped at 4.25. I guess it's just done. I'm

So I pulled it and i'm gonna chuck it. Thanks for the help though.
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Last edited by Kawi; Nov 10, 2011 at 04:50 PM.
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Old Nov 10, 2011, 07:39 PM
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The other option is to charge the #2 cell through the balance lead as a 1s cell.

Do you have a balancing charger? Did you balance charge it last time you charged it?
A cell can go low like that if the pack was unbalanced to begin with.
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Old Nov 11, 2011, 12:13 AM
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How do I do that? Yes I have a balancing charger, onyx235. No the pack has always been balanced.
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Old Nov 11, 2011, 07:56 AM
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See if you have a 2 pin male connector that will fit into 2 adjacent holes in the balance connector. If not, use 2 pieces of solid wire that will fit into the holes.

Add wires to the pins you have selected, red for +, black for minus and connect them to your charger.

Assuming you have a 4 pin connector, the black wire will be the starting point.
Cell#1 = Black wire is neg, #2 hole is +
Cell #2 = #2 hole is -, #3 hole is +
Cell #3 = #3 hole is -, #4 hole is +

You should check that with a voltmeter just to be sure. Be careful not to touch the voltmeter leads together or you'll short the cell.

Now push the neg pin into hole #2 and the positive into hole #3. Set the charger for 1s and 1A and charge.

But before you do all this, recheck the voltage of each cell. You said they were 4.25, 3.91, 4.25 I think. What are they today? If that middle cell has dropped more than the others it may not be worth the time to try to recover the pack.

BTW, 4.25V is too high.....4.2V is max and 4.15V is even better for long cycle life. Check those with a good voltmeter to be sure.
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Old Nov 11, 2011, 02:55 PM
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I just checked the battery. The first cell has dropped to 3.86 the second is 3.91 and the 3rd is down to 2.47

Not just that but I tested it a few times just to make sure and every time I attached the meter they would slightly change up or down. I think it's done. What's the best way to discharge it?
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Old Nov 11, 2011, 05:45 PM
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The easiest way is to hook it up to a 12V light bulb.
An auto brake light bulb or a 100W RV 12V lightbulb (same size as 120V bulbs) will do the trick.
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Old Nov 11, 2011, 06:29 PM
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Running it on a car or plane can damage them?
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Old Nov 11, 2011, 07:49 PM
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No, that would work. I would choose the car.
It will just trigger the LVC.......the problem would be with that 1 very low cell, the LVC will trigger with 2cells still having a charge in them.
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Old Nov 11, 2011, 10:39 PM
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The 3rd cell is down to 1.5volts. bizarre. I can put it on the revo Vxl and just not select lipo mode. I think the only difference is no lvc.
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Old Nov 11, 2011, 10:50 PM
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Be advised, it might puff, just a heads up in case the pack is a tight fit in the model.
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Old Nov 11, 2011, 11:03 PM
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Ok thanks.
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Old Dec 03, 2011, 01:53 PM
urs
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50-100

hi all
I completely ran down my spectrum-jr radio transmitter lipo batts...this I have done twice over the past 18 months...batt index showed zero nothing.the lipo charger showed the undervoltage screen even when I told it it was a 1cell lipo.I put the batt on to charge at 50m-iamp useing an old multicharger with several ,outlets with 25 50-100-500mi amps...left it on charge at 50 for 10 hours then at a hundred for 5 hours then connected it to my normal lipo charger which correctly recocnised it and corectly charged it...this brought my lipo back from the dead twice and have had no trouble since...this only in the low amp use of a transmitter...I wonderd if it would work with lipos I used for flying so IU didf some experiments on some old flight lipos...empteed 1-3s 2200 and 1 4s 3500 complete ly down first on a charger then useing a light bulb to finesh them of....then slow charged them at 100mi-am,ps for 10 hours and then fast charged and have since flown them 43 times since (the 2200 32 times the rest the 3500) and they give the same flying times as before...


draw your own conclutions give it a try ..all safty precautions must be aherd to--

urs
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Old Dec 20, 2011, 10:39 PM View Post
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Old Jan 13, 2012, 04:04 AM
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Hook your batt onto another 3s lipo for 5min than balance charge both. Works well.
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