Thermal Performance

FlightPower Thermal Performance

Thermal performance: Shown left is the temperature reached at 20C constant in an ambient temperature of 23 degrees C. This is the limit of the rated performance. For normal applications and for good cycle life it is recommended that the temperature be constrained to a maximum of 50 Degrees Centigrade at the end of a flight.
This is done by selecting motor and propeller combinations that normally draw less current than the limit of the rated performance. By definition a 1C discharge will deplete the full capacity of the pack in one hour. 20C therefore will deplete the pack in 1/20th of an hour or 3 Minutes (2.5 minutes in all practicality). Because it is nearly always desirable to carry a battery pack of sufficient capacity to fly the model for longer than 2.5 minutes, normally for 6 minutes for absolutely extreme performance (10C average with high peaks and troughs as in the above example) and very often for 10 minutes or more outside of the competition environment. For this reason, the FlightPower EVO 20 battery line is famous for arriving cool after delivering a very exciting performances. The other notable feature is that very often each cell in the pack will remain matched by voltage +/- 0.001 Volts after many successive flights. This is owing to the matching during manufacture. Over many 10s of cycles this can be maintained with the use of a cell balancer.