Lipo Storage Temperatures

[H3D]

I would like to store my lipos in a concrete hardboard (fireproof, hopefully) box in an unheated outside toolshed a good distance from my house. Temperature range out there is 60F to -10F depending on the weather. I suppose I could put a small electric heater in the box to mediate the low end. But is this necessary?

I searched on this topic and saw everything from "throw them in the freezer" to "don't freeze them".

Thanks,

H3D

 

[miuan]

My cell phone and camera lipos have been buried in deep freeze numerous times while still in operation. They've lasted for many years.

 

[dogman dan]

As I understand it, storing cold is ok. You just want to warm them up to room temp for charging them, and idealy for using them.

 

[Ykick]

I've been abusing a loose RC Lipo cell in my freezer (0-5F) to better understand cold weather performance. Basically, what DogMan said. Never charge when extremely cold and discharge should only be done at low currents if/when the cell is cold.

Once warmed up, below freezing cold storage doesn't exhibit any negative effects to my test victim.

 

[Lebowski]

cool so during winter when there's no e-biking I can store lipo's on the balcony in the freezing cold....

 

[parabellum]

If I understand well, if stored cold or frozen LiPos age slower (have longer shelf life).

 

[Ykick]

If I understand well, if stored cold or frozen LiPos age slower (have longer shelf life).

I have heard this too.

 

[Racer_X]

Is this the same for LifePo4 type batteries?

 

[Kin]

I know in general everyone seems to say cold is ok. I generally agree.

However, this is a hard thing for me to research on my own, because of mediocre google results, but could the cold temperature cycling affect the plastic membrane? From what I understand the membrane separating charged particles is made of plastics, which have a relatively high brittle-point [I forget the term for when something is cold enough that it's suddenly very susceptible to brittle fracture]. -10F is not *that* cold, but it is kind of cold that it might affect a very thin sheet of plastic. Maybe they design around this, but maybe they dont. For those on metric, I'd throw in a reminder that it's negative 23.3 Celsius.


While it would be best to figure this out conclusively, perhaps you could some very small heater and throw a blanket over the batteries+heater, for when the weather gets near that really cold range.

 

[dogman dan]

I wouldn't worry much, if the cold is still within the operating range the battery manufacturer specs. It's a pretty wide range, that doesn't mention what cycling at the extremes of the range might do. But I wouldn't worry that much about storing it at the low end of the spec.

Just warm it up some for cycling it, if nothing else, so you don't have too much voltage drop under load.

If it's really going to be that cold, you could put it into an ice chest to smooth out the temp range so it's always at the same temp day and night. Inside an ice chest, a very small amount of heat would keep them thawed. Ice chest and a tiny reptile heater?