Lipoly batteries - Question(s)

[beto9]

Hey, all electric wizzards (or not) out there:
Do Lipoly operate better, the same or worst in cold weather?
It seems there is a lot of folklore out there....

[bob forest]

I have a Lithium Ion in my 9Z transmitter, and I am lucky to get two flights in the very cold weather. Yes the cold does affect them.
Bob

[xed]

Had a Fromeco Lithium Ion pack, definitely lost voltage after being outside in the winter after 60 minutes. Did not trust them.

Lithium Polys should be affected in the same way. Proof is in the pudding.... Leave your cellphone out all night in your car and see how much talk time you get on it tomorrow.

I have had no problems with A123 batteries in the cold last winter, maintains constant voltage and if I'm unsure, I can recharge them, which warms them up in the process.

[turkana]

Yes Lipos are sensitive to cold. If stored in too cold conditions they will be damaged ! Also when flying in cold you should get them to temp bevor by putting them in your pocket or heating them otherwise. After flying remove the warm batt and let it cool of slowly if they cool of too fast lets say by -5 deg just beeing left outside, they will be damaged!And they should always be balanced charged and never overdischarged and when you store them for long time, never store them fully charged, they should be stored about 1/3 discharged. Hope I could help.

Regards Pete

[Burning Head]

Hey Turkana, I do thing you are right for the storage... but not for after flying time,because in winter batt never over heat like in hot summer time. For keeping warm befor fly that right to bros:cool:

[turkana]

I do not mean overheating in winter. After flying in general the Lipos gets warm.When it cools of too fast in winter it can happen ,that internaly you will get a condensation and that condensation will kill the batterie.Thats why cool them off slowly and do not just drop them in the snow :D


Regards Pete

[Burning Head]

You maybe right bros, but what I no about creation of condensation, is warm and cold...not sure. But, hot and mix with cold environement, that sure. I will see soon,that maybe wy last week I have some problem to ingni my recever.It take 3 min befor get the signal ? thanks:cool:

[Burning Head]

So if the battery coud be a problem in winter fly, what about the motor for shortcut or condensation... :cool:I will bet more on this problem :cool:

[turkana]

Motors do not care about the cold( I mean electric motors!),it s mainly the batteries and Beto was asking about lipos in particular.All batterys suffer in cold and do not perform, but since lipos are delicate as such one must take more care in the cold. Exept the Airthunder Lipos they are quite robust, they can actually be discharge completly without taking a damage, just awsome. I got 2 and will never look back.Going strong for over a year now. Airthunder rules! For more info here, read the bottom. http://www.airthunder.com/

regards Pete

[Burning Head]

Maybe electric chopper motor drain more from the lipo for keeping in the air then airplane do, so more drain mean hot battery and stuf .http://www.fastcats.ca/battery_care.htm but thanks:cool:

[zorba]

Peter is right about Air Thunder. I got two of them and accidentely discharge one of them (11.1) to 2v per cell.
My tp1010 charged it right up. The initial charging took longer that usual but they got charged.
Is not just the lipo's that will not perform in winter also the servos.
Last year when we went flying ant the field the servos on one of the choppers would hardly move, of course it was windy too and that didn't help.
So, get your self a cover of some sort and cover your heli to keep it warm till you fly.
Cheers

[Mick]

Being an all electric flyer at the moment I consulted Flight Power for some advise and got the following response:

Hi Mick,
Using LiPos in cold weather can be very finicky. IF the core temp of the cells is below roughly 60 deg. F & put under a heavy load they can sustain damage. I highly recommend using something like a thermoelectric cooler that will keep the batteries heated before use & warm through out the day.
--
Thank You,
Steve Rogers
FlightPower USA
919-741-6310
www.flightpowerusa.com
www.marine-power.com
www.trakpower.com

Other websites and forums state that they must not be used below 32F at all. Therefore the key is to keep the batteries in a warm environment, a warmer as above sounds good, and then fly immediately you fit them to the aircraft. Some form of insulation might also be a good idea in really cold weather, then as stated above keep them warm after the flight, another warmer or even a pocket?

One word of caution about batteries in pockets, I made the mistake of putting a 10 cell NiCad in a pocket and the wires shorted out on some coins, the battery got very hot, very quickly and I managed to avoid a burn by quick action, with a LiPo it could have been very dangerous so I now use better insulation and much greater care. Be safe, fly safe.

[bob forest]

Re having problems with servos, in cold weather,has not happened to me. I have been flying the last 6 winters, in very cold and windy weather. I have never had a servo freeze up on me. When on the lake flying off the ice. The plane sits there all afternoon. We have flown on sunny days, which helps the interior of the plane getting warm, and on cloudy days with no sun, and still no problem. Nicads int he plane, they seem to be ok in the cold. But personnally have not heard of any servo problems in the cold.

[Andrew Fernie]

This is a problem for me for the indoor flying during the winter as I go straight from work. I have always taken my LiPos into my office to keep them warm, but leave the aircraft (and radio) in the car. When it is really cold I let the aircraft and radio warm up for a bit when I get to the gym. The NiCd in the radio seems to be O.K. with this.

Andrew

[Burning Head]

I allready buy some hunter heat pack.I no this pack coud come very hot even dangerous for burn on direct skin. I will bring and try one tomorow rap in a old T shirt for control the heat and see. That coud be great if it work other way winter will be long:cool:

[turkana]

Well we sell these tiny heaters, some chemical in tiny bags, when you crack them they become warm and stay warm for 6-8 hr.So I guess when you take a thermal bag or lunchbox with you, you could put one of them with the lipos into the bag.Or you could stick one to a lipo, the only problem I see is that you only heat one side of it.
Also Helipilots should be carful in winter, if your frame is plastic, carfull it just chatters at low temps and you should be really sure if your Gyro can handel these low temps. bevor flight be sure to switch on power for at least 3-5 minutes to have the Gyroelectronics adapt to the temps.Cheaper HH gyros become very erratic and slow.

Regards Pete