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simibill
10-15-2005, 08:04 PM
I have a Multiplex LN 5014 charger. When charging my LiPo pack the operating instructions says when the cell voltage is about 4v the charger switches over to constant voltage and charging is terminated when the charge current falls below 100mA. With my 3s pack the voltage reaches 11.97 and the charger is still going. I got tired of waiting and stopped the charging. How high can the voltage go before the charge current falls below 100mA?

Red Scholefield
10-15-2005, 09:20 PM
I have a Multiplex LN 5014 charger. When charging my LiPo pack the operating instructions says when the cell voltage is about 4v the charger switches over to constant voltage and charging is terminated when the charge current falls below 100mA. With my 3s pack the voltage reaches 11.97 and the charger is still going. I got tired of waiting and stopped the charging. How high can the voltage go before the charge current falls below 100mA?

Somewhere between 12.2 and 12.6 for a 3S pack.

simibill
10-15-2005, 09:28 PM
Red,
Thanks. How long should it take to reach 12v from a 8v discharged pack? Seems to me to take 30 minutes or more.

Red Scholefield
10-15-2005, 09:46 PM
Red,
Thanks. How long should it take to reach 12v from a 8v discharged pack? Seems to me to take 30 minutes or more.

You discharged a 3 cell pack to 8 volts? That is close to the disaster zone. Depending on the rate you are using it should take at least an hour when charged at the C rate.

everydayflyer
10-16-2005, 01:02 AM
Most 10C and better LiPolys (current generation) have no useable capacity left at 3.3 volts per cell under a moderate load (5C plus).
LVC should be set no lower than 3 volts per cell. Open (resting) volts after a flight should be at least 3.3 volts per cell and 3.7 volts per cell is much kinder on your LiPos. With many setups the difference between having your packs read 10 V after a flight instead of 11.1 volts is about 20 or 30 seconds of flight time. Be kind to you packs and land a bit earlier.

Have a look at the attached graph and not that at 10 volts under load there is less that 5% capacity remaining.

Charles

hoppy
10-16-2005, 01:38 AM
Time for a full charge at 1C with a CC/CV charger? About 1 1/2 hours

compflight
08-11-2007, 11:55 AM
Does charging at the 1c 1.5c or 2c have a significant effect on battery life expectancly or discharge rate availabiltiy?

jooNorway
08-11-2007, 07:54 PM
Does charging at the 1c 1.5c or 2c have a significant effect on battery life expectancly or discharge rate availabiltiy?
Yes, absolute!
If you have the time to charge at 0,2C instead of max (usually 1C) it will help prolonging life cycle a lot.
But if you discharge at close to max it would be worn out quite fast anyway.

For the Antares-project the charge-time is 8 hours. Their LiIons had 1770 cycles without noticeable loss of power...