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Old Jul 26, 2013, 06:23 AM
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United Kingdom, England, Dorset
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One cell different voltage

Hi,

I bought two Turnigy nano-tech 3.0 25-50c batteries for my T-copter, and an IMAX B8plus Charger/Discharger 1-8 Cells.

First charge of one battery, I used 'CHARGE' instead of 'BALANCED CHARGE' afterwards one of the three cells has slightly different different voltage. Since then I've charged it with balanced charge, and it still stays different. The other battery has always been charged balanced and all cells stay the same.

Is there a way to bring the first battery cells to be all the same?

Cheers, Camerart.
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Old Jul 26, 2013, 10:11 PM
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How much difference are you showing? Also, are you using a separate device to measure the cell voltages, or depending on the charger display?
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Old Jul 27, 2013, 03:19 AM
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Originally Posted by Wintr View Post
How much difference are you showing? Also, are you using a separate device to measure the cell voltages, or depending on the charger display?
There are two batteries. Both read 0.01v difference on one cell.

I have a plug in voltage read out, that shows each cell voltage and total voltage. I also have an alarm that beeps when the battery is low or faulty in flight. This beeps after battery 1 'only' has been charged, until it is working then stops. It's only this alarm that has made me post this.

Cheers, Camerart.
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Old Jul 27, 2013, 09:21 AM
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That's too small a voltage difference to worry about, IMO; less than 0.25% difference, which is about the limit of your measuring devices, possibly less. The more important question is, what is the voltage on each cell when you plug it into the alarm? I assume the battery has rested several minutes when you do this, so that is when you should re-check cell voltage, not when it comes off the charger. If you have a weak cell, it may drop in voltage enough to trigger the alarm. I have an alarm that will sound until I start actually using the battery, and I attribute that to the alarm somehow being more sensitive to voltage differences when the battery is above 4V.
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Old Jul 28, 2013, 03:53 AM
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Originally Posted by Wintr View Post
That's too small a voltage difference to worry about, IMO; less than 0.25% difference, which is about the limit of your measuring devices, possibly less. The more important question is, what is the voltage on each cell when you plug it into the alarm? I assume the battery has rested several minutes when you do this, so that is when you should re-check cell voltage, not when it comes off the charger. If you have a weak cell, it may drop in voltage enough to trigger the alarm. I have an alarm that will sound until I start actually using the battery, and I attribute that to the alarm somehow being more sensitive to voltage differences when the battery is above 4V.
Ok, I'll take it more as a sensitivity issue than a problem.

Thanks, Camerart
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