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Old 09-06-2008, 05:06 AM   #1
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Default Finding out how many mah left on a battery pack

is there a way to find out how many mah are left on a battery pack after a race???sometime people mix by mistake full charged batteries with half charged one. is there a way to check the mah on the fly???
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Old 09-06-2008, 06:40 AM   #2
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You cannot check capacity of an unknown battery, Without charging or discharging it, which in your case is not feesable.

You can check the voltages though: choose the pack with the highest voltage. And over time, as you check the voltages of packs, you'll see that (FOR EXAMPLE), 8.2v is fully charged, or less than 8 is discharged. You'll notice general resting voltages that can indicate charged, or discharged, but you cannot precisely predict Mah.

Hope i helped, John.
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Old 09-06-2008, 07:47 PM   #3
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Voltage is the only way to guess at the pack capacity without the use of a discharger.. The higher the voltage compared to similar packs the greater the charge left in it.

Packs can vary in labled capacity by a little, so this method would be ok for comparing 4200 adn 4600 together but not 4600's to 3300's./

NiMH cells can sit stable up to 1.4V per cell after the "surface" charge fades.

So if you are checking 4-cell packs and you have one at 5.34V, 5.12V and 5.48V, Your best bet is the 5.48V pack since it will be the most full pack compared to the other packs.
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