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Old Mar 20, 2016, 05:22 PM
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mAh Question

I'm flying a plane with a 6s, 4000mAh battery. After a flight time of 8 minutes I am putting 2050mAh back into the battery. Does this mean I can add 25% more of flight time.??
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Old Mar 20, 2016, 05:41 PM
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if your going by the 'use max of 80%' rule xD
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Old Mar 20, 2016, 05:49 PM
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Your only using about 50% of the batteries mah capacity. You can safely use 80%. That means you can use 3200 mah.

Keep adding to your flight times till you are replacing 3200mah.

Tom
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Old Mar 20, 2016, 06:06 PM
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Remember, one hitch to using the "back-in mah" to calculate % used, is that it assumes the battery never loses mah due to aging.

IMO, it's much better to use 3.7V/cell (resting - after flying) as the min low voltage limit. That is about the 80% of actual capacity.


Avg Resting V % Remaining Capacity
By cell
4.00V--84%
3.96---77%
3.93---70%
3.90---63%
3.86---56%
3.83---48%
3.80---43%
3.76---35%
3.73---27%
3.70---21%
3.67---14%
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Old Mar 21, 2016, 04:42 PM
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Great reply hoppy.!!!

Thanks to all. I'll go down to 3.70 per cell.
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Old Mar 21, 2016, 05:16 PM
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There's also some loss that occurs within the battery when charging. You can see that if you do a charge from a particular voltage then use the charger's discharge function to the same voltage. You'll get a slightly bigger number going in than going out. In any case 3.7V resting voltage is the best thing to go by. A higher voltage means you've got some amount of charge left you can utilize as indicated by the chart above.
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