agentfox1942

Anyone have any history or info about storing LiPo's in an unheated garage over the winter? Isn't cold better for batteries? I remember as a kid storing NiCad's in the freeze, but that might be old school. I work in my garage which is unheated. doesn't really "freeze" per se, but it gets dang cold. I've left a cup of water in there and it never froze. I assume my power supply and charger may work better being cooler, as long as it is dry, correct?
Any input would be great.

Thanks

Duster_360

iTrader: (21)

I've got 8 lipos sitting in the veg crisper in my soft drink refrig atm at 39F. I read about some storing in a deep freezer and thats colder than your garage. Hyperion's recommendation for storage bottoms at 37F though reason mine are where they are.


I think you're ok if its not getting cold enough to freeze water though. the cold may improve you chargers and PS efficiency a tic or so but I'm not sure you'd notice. If you have a wattmeter though that'd be an interesting ques to answer.

agentfox1942

thanks duster. I wonder if the LogViewer would be able to chart any differences? My iCharger 208B works with it and I'm getting to know it little by little. Although I really wish you could set the 208B via the computer. Stepping through the all those menus is a pain.

Duster_360

iTrader: (21)

No, wouldn't see it cause any change in efficiency would be on the input side of the charger, logview sees just the output side and it wouldn't be apparent.

You'd need to charge a battery inside with a wattmeter in the line between the PS and charger, then do it again outside (after the temp adjusted to the cold) and compare wattmeter indicated watts. My guess it would take less watts outside in the cold, but have no feeling for how much less. I need one, just haven't bought it yet, but now I'm curious....

Save your money, the only charger that you can truly control from the PC is the Powerlab 8, and its expensive since you have to buy all their cables and adapters, nobody else's stuff can work on their charger. I went thru this with Hyperion and I haven't even loaded Logview for my 3010b.

skree

i wouldn't store your psu and charger out in the workshop - that's just asking for condensation

good thread though, needed this answering myself as i charge outside and we're uner 3' of snow at the moment lol

pyro18t

iTrader: (1)

I have no idea as far as storage goes, but I know for a fact when I was flying RC planes in Germany when it was cold out side my plane had very little punch and shorter run times. So I did a test, I had 6 Lipos all 2200mah 30c packs from the same company. I went to my flying field and let 3 batteries sit outside for 30min, and 3 in the car with the heat on. The heated packs were TONS I mean TONS faster than the ones that were cold soaked. I also put my WATTS UP METER on it as I flew and measured peak amps. I don't remember what the actual amperage was but the heated packs were about 7-10amps higher. That's a lot when your only pulling 35-45amps! OAT was about 30-35*F. Non of the packs received any kind of damage and worked fine after the test.

Jay

agentfox1942

Pyro, interesting input. I wonder if that is what makes it good for storage, the cold temps that is. I mean, your evidence shows that the cold limited the output, which would suggest that maybe they are "hibernating" for lack of a better word, when the batteries are cold. Warming them up, releases the flow. So maybe it's good for storage, but not prior to running. Although I would assume charging them prior to use would warm them up.

Dave H

Pyro is correct, and you are on the right track until the last comment. Do not charge cold, not good for the lipo, charge state varies with temperature, and it won't warm them up much anyway. Let them warm back up before charging. In a sealed bag to reduce condensation issues too. Store and warm them up in the sealed bag.

chb

I agree with some of the comments above:

# low temperature and 40~50% charge state is very good for Lipo/Li-ion battery ageing (if you don't use you lipo for a while, do it)

# low temperature is NOT good for lipo operation as it increases internal resistance (hence loss of power)

Lazer Guy

iTrader: (1)

A couple years ago I did a lot of E-mailing to manufacturers of lipo's about the best temp's to use them at in the winter.

The collective answer was.
Never use them if they are less then 60*F.
Keep them at the same temp all day when using them.

I temped my lipo's after every race and found them to be 85*F. +/- 5* at a cool indoor track in winter.
After trying many different things to heat my lipo's to ONLY 85* I made a box and used a reptile/amphibian terrarium heater.

I don't use the heater box I made any more, (it's one less thing to pack up) but I do put one 12 hour hand warmer packet in with my lipo's before I leave to go to the track and keep them in there all I can on a cold day.

Do I fell this helped me in any way It did keep my I.R. lower.
If nothing else I feel better about my lipo's doing it