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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Peter Germann on July 14, 2016, 05:21:59 AM

Title: Battery Useful Life?
Post by: Peter Germann on July 14, 2016, 05:21:59 AM

- ThunderPower Magna 2700mAh 5S 70C
- Battery temp. after landing 35°C / 95°F  (ambient 75°F)
- Cooled-off before charging
- Balance charged at max. 4.0 amp (1.5C) to 4.2 V/cell
- In-flight discharge as per diagram attached

Three of my total of six packs have now reached 60-70 cycles showing 18.5 V after landing idle voltage.

How many more cycles may I expect to reach before the lowest in-flight (loaded) voltage drops below 3.4 V/cell or 17.0 V ?

Title: Re: Battery Useful Life?
Post by: Motorman on July 14, 2016, 07:03:23 PM

28

Title: Re: Battery Useful Life?
Post by: Wolfgang Nieuwkamp on July 15, 2016, 03:16:22 AM

Peter,
in my opinion, the best way to monitor the condition of Lipo´s is to measure the internal resistance.

Title: Re: Battery Useful Life?
Post by: Martin Quartim on July 17, 2016, 09:11:02 AM

My friend here already put 250 cycles on his TP Pro Lite.  At the circle he charges at 4C and lands with 20%. His Batteries are in perfect condition and we believe he will get more then 300 flights out of it.

He did break in the Battery charging 1C and discharging 3C.

Martin

Title: Re: Battery Useful Life?
Post by: Peter Germann on July 26, 2016, 07:39:49 AM

Quote from: Wolfgang Nieuwkamp on July 15, 2016, 03:16:22 AM

Peter,
in my opinion, the best way to monitor the condition of Lipo´s is to measure the internal resistance.

Thank you Wolfgang. As my charger does not offer IR readout what I intend to do instead, is flying the batteries until the castle edge log shows 100% power out to motor in the last (clover) manoeuvre.