Lipo batteries stored below freezing...

[ParkeFlyer]

It's suppose to get below freezing tonight... (I'm in Texas, this is a BIG deal). I store all my plane gear in a detached garage that is not that different than storing it in a shed. If it is freezing outside, it's freezing inside the garage.

Is it a problem letting the lipo batteries freeze??

--Thanks--

edit: After posting, I did a little more research and several places recommend NOT letting your batteries freeze.

 

[Pilot Scott]

Like most batteries, the temperature of a Li-Po has an impact on its performance. Consider that batteries rely on a chemical reaction in order to produce a current – therefore a low temperature reduces the speed of this reaction and a reduction in overall pack performance may be observed on a cold day. Allowing a Li-Po pack to freeze is certainly not recommended, as this would almost certainly damage the pack.

 

[Pilot Scott]

I'd bring them in. One good and safe way to store them in your house is to use a military ammo can. I like the 50cal size. It's also a safe way to transport them. I keep mine stored at all times in one. Careful with the lip on the cans. They are waterproof so they have a fairly tight clearance and will cut your wires like scissors. You can pick them up at an Army/Navy store (military depot) or we have them here locally at a place called ACE hardware.

 

[pgerts]

I have had LiPo stored in -20C (-4F) without any problem.
You must be sure that there is no ice on the battery (moist), but that will normally not be a problem in a closed shelf or garage unless you are moving your wet car in and out.
As Scott says - bring the batteries in for charging and keep them warm (in your pocket) until time for flying. Dont leave the battery in the plane if you are ging to fly another round with the same battery as it will lose a lot of power if it gets cold.
This is not an electric - but it is always easyer to take of pic of someone else.
Using a LiPo with a C-rating higher than 50 is a lot better when it is cold than C below 20 as the cheaper batteries suffer a lot more in the cold. But it wont do any difference just for storing. Remember not to store fully charged LiPo for long time indoors or outdoors.

 

[FlyingMonkey]

I am so glad I live in Florida!

Thank you for that picture pgerts, it helps me appreciate how much I don't miss snow! 

 

[Jeffrey Saelee]

Haha, you lucky monkey! I HATE the below zero temperatures here.(ok, that was a little off topic--but here comes the on-topic)
When I had my PZ Micro T-28, I couldn't fly for more than a couple minutes, because: 1: the Lipo would get too cold and motor wouldn't work and 2: my fingers would get cold .......but that was just a 1S 120mAh Lipo

 

[Klonas]

Remember not to store fully charged LiPo for long time indoors or outdoors.

Off topic but I have a question.
What do you mean by long? Week? Month?

 

[pgerts]

@ Klonas
I am doing it totally wrong!
I normally have my batteries charged as i want to fly when i get an opportunity ;-)
LiPos should be stored at a voltage close to the nominal (3,8 - 4,0 volt per cell).
I suppose long time is the winter period when smart pilots stay at home storing the planes.

 

[colorex]

What about high temperatures? What is too much for a lipo?

 

[wadsie]

i had a battery in my phone and didnt touch it for a couple of days, after those day i went to get my phone and the back ad fell off, so when i went to pick it up i notice the battery was puffed up and that is what cause the case to fall of dunno if it was a lipo but the tempreture was about 40 degrees celsius so that would probably explain what happend.

 

[Pilot Scott]

Most manufacturers consider storage as 3-7 months. My rule of thumb is 3 months although I have had a few with a full charge in excess of a year and she fired right up as if it were brand new.

Off topic but I have a question.
What do you mean by long? Week? Month?

 

[pgerts]

What about high temperatures? What is too much for a lipo?

I know that some competition pilots heat their LiPos to 40,0°C just before flight.
But keep the ventilation and cooling of the battery sufficient when it is a warm day.
Keep the battery insulated not to get cold when it is cold outside.
Store the battery cold but dry!

 

[rogue-insight]

Lipo batteris do NOT have water or such as the electrolyte, so the freezing point of water is irrelevant. In fact, they use lithium organic salts as the electrolyte, and these have a much lower freezing point than water. Manufacturers will actually recommend putting them in the freezer at 40% state-of-charge to maximize their shelf life. True cold hurts performance, but it's good for storage!

 

[colorex]

Lipo batteris do NOT have water or such as the electrolyte, so the freezing point of water is irrelevant. In fact, they use lithium organic salts as the electrolyte, and these have a much lower freezing point than water. Manufacturers will actually recommend putting them in the freezer at 40% state-of-charge to maximize their shelf life. True cold hurts performance, but it's good for storage!

Good to know! Thanks for your input!