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Electric Stunt => Gettin all AMP'ed up! => Topic started by: paul winter on December 06, 2012, 01:51:36 AM
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hi all
a question for the boffs
Are electric lipos affected buy the extream cold, as in the UK its on freezing but no wind
so i want to know is it safe to fly ???
Paul
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LiPos are affected by the cold.
I cannot give you any specific data, though. In freezing temps (down to about -10C), I've only flown R/C parkfliers. My procedure was to keep the LiPo in a warm place until I plugged it in just before flight. I also restricted airflow by taping over the intake which also helped keep the snow on the outside.
You might want to experiment a bit: flying without putting the airplane in too risky attitudes.
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A good "warm place" is a shirt, pants, or inner coat pocket. Or inside your car if it's accessible and warm.
That works for glow start batteries, too -- they work much better out of a pocket than out of a freezing tool kit.
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A good "warm place" is a shirt, pants, or inner coat pocket.
Just check there's nothing in the pocket that COULD short the pack ~^
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Just check there's nothing in the pocket that COULD short the pack ~^
At least then you won't be cold.
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Paul,
I use a metal ammo case with vertical separator's to hold the batteries, a side benefit is that the case can be set in the sun and it warms quickly. I have also slipped hand warmer packs inside the case. Although it doesn't get to cold here in FL at times for the King Orange it has dropped into the upper 30's which will reduce capacity. On my profile ship I have put a foil rap around the pack since they hang in the breeze. I also like to keep the case inside the warm car or building until it's time to fly.
Best, DennisT
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From everything I have read, LiPo's perform best at 110 degree F for both charge and discharge. Not much of a problem in the summer, but in winter self heating should help if they start warm and you restrict the air.
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A "Little Igloo" cooler will also act as a good heater. I warm "cold/heat" packs in the microwave and put them in with the batteries. I think I got packs from Walgreens when I had knee surgery.
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Electrics use more energy on cold days and on calm days. Do slow, short flights to see if you have enough battery capacity, especially if you have an unfamiliar propeller. This reminds me: I have a battery I'll sell cheap.
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Even the same energy in cold day with frozen battery with higher internal resistence and thus lower voltage means higher consumption of mAh :- )))