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Lipo Balance Delta Voltage Error

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Lipo Balance Delta Voltage Error

Old 01-26-2020, 04:19 PM
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Default Lipo Balance Delta Voltage Error

I have a ProTek Prodigy 610ez Charger with a ProTek 2S 120C Si-Graphene Lipo with roughly 15 charges through it most likely.

My cells unbalanced somehow during my last run they read:

3.20V and 3.42V

the IR is roughly 6-7 mohms for each cell.

When attempting to charge my charger wonít do it since the cells are so unbalanced. I canít imagine this is grounds for tossing the battery since it never fell below 3V per cell and they are so new still. Any ideas?
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Old 01-26-2020, 07:45 PM
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Can you activate a discharge operation?
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Old 01-26-2020, 09:01 PM
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Tried again to see if there would be any difference and the cell went back up to 3.32 and 3.42 after a few hours and the charger was able to balance it accordingly. Not really sure what happened here to be honest hope someone with experience can chime in and help people out for the future!
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Old 01-26-2020, 11:19 PM
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I suspect one cell is dying. Did you accidentally over discharge the pack? This can happen temporarily under high current draw, causing the voltage to drop below safe levels briefly. The voltages can recover once the current draw reduces/is stopped.
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Old 01-27-2020, 06:16 AM
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3.20V + 3.42V = 6.62V at rest, this tells me you have your LVC set too low, I would encourage you to MAX your LVC setting on the ESC, then your cells shouldn't go that far out of balance in the future.

Another trick is to charge the pack in NiMh mode for about a minute, very important not to go more than a minute as there is no shutoff peak detection with LiPo packs... anyway, when you "boost" in NiMh mode this should help level out the voltage of the cells then switch back to LiPo mode to finish the charge.
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Old 01-27-2020, 08:48 AM
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rad there is no real way to say what your packs issue is.. but your lvc is way low.. I made one of these years ago to help A charger out and the Charge in Nixx mode for a short time does work. but you have to watch cell and charger voltage while doing this the 1minute thing I dont like as a NiXX mode voltage can jump in seconds(watching is best).. might try and make whats in pic to help next time I use a lvc alarm that I can set to help me keep my batteries above the 3.37voltage level.

thats a deans and a servo extension with only the + - wires..
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Old 01-27-2020, 09:14 AM
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I may have discharged too much. This is the first time Iíve ran any pack long enough to enter the LVC on my Esc which was just the stock value. I will increase that to itís max which I believe is 3.4V per cell (Hobbywing Justock).

my car went into LVC and then I drove it down the straight to grab it off the track, Iím assuming this was my problem of pushing the battery past itís limit. I will make sure to monitor this pack closely in the next few cycles to assure that it stays healthy.
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Old 01-27-2020, 04:44 PM
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The fact that you corrected it right away saved it from any minor/major damage, if it was left like that the damage becomes more permanent. Check resistance of the cells.
The dynamite passport ultra p2 Charger I use has a LVC of 3.2 per cell and my ESC is set for 3.2v per cell, however one time it was slightly lower and the charger idled at .5 amp trickle charge until both cells were above 3.2 and went into a storage charge at 5.0 amps, I let it finish the storage mode then went into balance mode to completely charge. Hasn’t done it since.
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Old 01-27-2020, 05:44 PM
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I have the prodigy 610 also and it does the same thing when there is to much delta between the cells. It's unfortunately an internal setting they determined and non adjustable. When that happens I just ask one of the guys at the track with a different charger to partially charge my pack to a point where the delta is reduced. Buying an icharger to get rid of this problem. Going to keep the prodigy as a spare
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Old 01-28-2020, 07:34 PM
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Bill, as usual, is right. Battery voltage usually recovers within less than a minute. So if it's 3.2v resting voltage, it was being pulled down much more than that during use. Given the IR of both cells is the same, you probably didn't do much if any damage. LVC should be ideally 3.5v/cell and no less than 3.4v/cell.

Try doing a non-balance charge and if necessary disconnect the balance adapter. Let it run for 10-15 mins then switch to a balance charge. If the charger complains the voltage is too low for Lipo, you can run it on NiMH setting for a couple of minutes to get the voltage up switch over to the lipo charge.
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