Lipo’s in the cold???

[eeeyal]

I’m running Align 7.4V 1100 mAh 9C packs on my trex 600 to power the servos. I only get one flights worth out of a battery pack per charge :arggg: . It’s about 40-50°F where I live; could it be the cold that is effecting the life of the packs?

If so, what cells are you running in the cold? What do you think of li-ion cells?

[Coolice]

Hey,

In the UK during the winter months, we have found that our flight LiPo's are best stored in our pockets/car to keep warm until we are about to fly.

It is known when LiPo's are cold their voltage can drop easier and sooner than normal, with your main power LiPo this isn't a problem as a minute or two of flying soon brings them up to running temp.
This is seen more if you have a voltage guard fitted to the model as we do, during the first minute of flight on a fresh pack the low voltage warning activates. Fly around for a while with it on, land for a few seconds so the load disappears before powering back up again and you then fly a full flight before the warning to land comes on again.

However your Rx. LiPo will not have the same loads to warm it up in the same way.

A little experiment you could try is to warm the pack in your car or pocket before you fly and see what sort of power/duration you get from the pack then.
.

[eeeyal]

I tried keeping the packs in my pocket before flights … like you said there is no load on them so they don’t stay warm :( . I was wondering if you know anything about li-ions and the way they react in the cold. Also, do you have any ideas about good Rx packs for cold weather from experience? I just don’t want to take a chance with different cells and loose the model because of a dead RX pack.

[Pinecone]

For Rx pack I would make a foam sleeve to stick them in. Warm in your pocket (or car) and then put into sleeve to hold the warmth. Lots of plank guys do this during the winter.

[Pinecone]

For Rx pack I would make a foam sleeve to stick them in. Warm in your pocket (or car) and then put into sleeve to hold the warmth. Lots of plank guys do this during the winter.

[eeeyal]

ok, thanks.

[Coolice]

Hey,

I'm pretty sure Li-Ions react the same to cold weather, but I am not certain. Essentially the cells are the same but with different chemicals and so this may help.

As for a good Rx. pack, on the Turbine predator I have I am running Fromeco regulator with a ReLions Li-Ion Rx. pack and that performs well in all weathers. But we have to remember the load imposed on these packs isn't as great as say a flight pack.
I am just in the process of going the same route on my Freestyle as I trust this above regulator combo.
.