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Old 03-31-2006, 01:10 PM   #1
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Default Battery capacity

When a battery is rated at 3300 mah, what should I see as the charge mah going in on a digital peak detection charger (I'm using a Reedy Quasar Pro set to 5mv/cell)? What should I see for output when I measure it at 15 or 20 amps discharge rate?

None of my nimh batteries seem to be taking anywhere close to 3300 mah charges, and they sure aren't outputting 3300 mah when discharged at 15 amp rate to 0.9 volts per cell. These are only 3 month old batteries. What am I doing wrong, or what is normal?

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Old 03-31-2006, 03:42 PM   #2
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MAH input is going to depend on if you are discharging them all the way down or re-charging them while they have a partial charge still in them.

If you discharge them all the way down to .05 then take them down on a tray to zero then when you charge them you should see a MAH number in the 3400-3600 range.

If you are not fully discharging them you will not see numbers that high since the cell is still partially charged at the time you charge them.

As for you MAH output at discharge the 15amp. with a .06 cut off is a very odd discharge. Most matchers recommend at least a 30 amp rate with a .05 cut off.


So again your numbers will be low because at the .06 you are not fully discharging the cell...
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Old 03-31-2006, 06:31 PM   #3
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The MaH could also change with what amperage youre charging your batteries at. The higher the amperage the less MaH you will have (or run-time) but you'll have more power. It could also be false charging as well. But yes, try what imprsm said by putting your batteries on an equalizer before your charge, on a discharge after and equalize them after as well. That will help tremendously too. Also keeps your batteries in tip top shape

Hope this helps,
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Old 03-31-2006, 10:47 PM   #4
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I don't know what I was thinking. The Reedy charger discharges them to 0.9 volts per cell at up to 20 amps rate. So the 0.9 v/cell is what is probably holding them from dumping all their capacity? I guess I need an equalizer tray that takes them down further.
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Old 04-01-2006, 10:17 AM   #5
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On the contrary,
My 3 months-old-unused match (SMC GP3300 old-30-amps discharge) performs out of my IB3800 matched cells.. I'm using LRP Pulsar Comp at 6.0, peak detect at 45mv

Check the pics. Any comment ?
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Battery capacity-bat1.jpg   Battery capacity-bat2.jpg  
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