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BAttery Resistance Question

BAttery Resistance Question

Old 01-24-2007, 09:57 AM
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I have some IB3800s and I just charged the pack up and then let it cool then discharged on my DPD, the problem I have been noticing is that the resistance of one or two cells is much higher than others, for example I have one pack that 5/6 cells are 1.8-2.7 and then one cell had a resistance of like 6.0...Could this be right? Thanks and please let me know what I can do to lower this or is it just the DPD misreading...
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Old 01-24-2007, 10:05 AM
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Keep in mind this measure is in milliohms, or .000. So a 2.5 mohm rathing is .0025 ohms. Thats a very small number so it can be greatly affected by the contacts of the DPD or the way the battery bars are soldered. I have a Dyna pulse and one of my 4 cell pack gave an ir of 24 mohms compared to another of 13. I found a poor solder joint, fixed it, and now that pack reads 15. Comparing this to a Trinity Spec pack, which uses those cheap spot weld type tabs, has an ir of 53.
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Old 01-24-2007, 12:45 PM
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What Gubbs.3 said is correct The resistance inthe cells will get higher with age and some will get bad sooner then others, but the contacts can also be dirty or loose, and you then get a poor connection and this will cause the cells to give a higher reading.
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Old 01-24-2007, 01:22 PM
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Originally Posted by MEGAVOLTS
What Gubbs.3 said is correct The resistance inthe cells will get higher with age and some will get bad sooner then others, but the contacts can also be dirty or loose, and you then get a poor connection and this will cause the cells to give a higher reading.
What would you guys recommend me doing to try and get a lower reading? Should I just leave it as is or should I try to resolder the joint? Also I was using the deans bars, does it matter if the pos bar side goes to post battery terminal?

Last edited by jeffbhhs; 01-24-2007 at 01:49 PM.
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Old 01-24-2007, 02:11 PM
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Ceck your solder joints on your pack and clean your pins on your discharger. I use motor cleaner on a Qtip, This seems to work very well. If the reading is still the same then you probably have a bad cell.
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