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Joined: Sun Jun 03 2007, 07:29PM
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There might also be a safe minimum amount you can discharge a battery pack to without risking permanent damage due to one cell being weaker than the rest, before it overdischarges or reverse charges. In practice you may not be able to use all the capacity it says on the label. You say "At 1 to 3C" but that's still a little vague and could be in fact nearer to 3C, if the manufacturer justs wants to make his product look good. Batteries can put out a lot of current intermittently. But at 1C continuous I'd it expect it to be a little less.
I would put more trust in a voltage monitor/Alarm.
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Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
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Electra wrote ...
There might also be a safe minimum amount you can discharge a battery pack to without risking permanent damage due to one cell being weaker than the rest, before it overdischarges or reverse charges. In practice you may not be able to use all the capacity it says on the label. You say "At 1 to 3C" but that's still a little vague and could be in fact nearer to 3C, if the manufacturer justs wants to make his product look good. Batteries can put out a lot of current intermittently. But at 1C continuous I'd it expect it to be a little less.
I would put more trust in a voltage monitor/Alarm.
These are good points, but i know these batteries are good to 25C long, 50C burst discharge, and 10C for long duration if needed. as long a we keep about 25% capacity remaining at 3.7V unloaded, we can charge to 4.2 volts per cell in parallel and discharge in series, without puffing or explosions.
our chargers show us a counter with the charge put back in, so we know that 75% input number ( in mAh) for the next flight. We do measure the exact voltage on every charge before flight, per cell, i like to have my cells within 0.08v of the others unloaded after rest.
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Please check my math
