Battery Shelf Life and Temperature

[LightofMine]

According to the temperature and storage graph on Energizer.com the Alkaline D, C, AA, AAA batteries would have a shelf life of 7 years. However, after the 7 years they would be at 85% power and that is only if they are keep at 68 degrees Fahrenheit. How many people do you know that keep their house at 68 degrees F all the time? I sure don’t, my house stays at about 75. So does that mean the use by date they put on the batteries is just advertising and not the real world? The higher the temp gets the shorter the shelf life. According to the graph, at freezing (32 F)the shelf life goes up to 9 years with 95% power left in the battery. Do any of you put your batteries in the freezer? If not why? Is there any reason I would not want to freeze my batteries then thaw them out slowly when I anticipate needing them?

James

 

[Doug Owen]

You'll note from the graphs "Service Manitenance Storage Temperature Effect" that raising the temperature from 20 degrees C to 40 cuts the time to 90% capacity in half. That's alot of degrees (to 104F). I doubt your house really *averages* all that much over 72 does it?

Yes, some folks do store their spare cells in the refer or freezer (a left over from zinc/carbon cells that were much worse), but most 'in the know' don't consider it worth the effort any more.

Doug Owen

 

[Double_A]

!!!!! DO NOT FREEZE YOUR BATTERIES!!!!

Batteries in the freezer can swell and rupture internal seals causing them to leak and fail when thawed out!

There is nothing to be gained from doing this over just putting them in a zip lock in the fridge.

GregR

 

[Doug Owen]

[ QUOTE ]
Double_A said:
!!!!! DO NOT FREEZE YOUR BATTERIES!!!!

Batteries in the freezer can swell and rupture internal seals causing them to leak and fail when thawed out!

There is nothing to be gained from doing this over just putting them in a zip lock in the fridge.


[/ QUOTE ]

Don't tell me, tell Energizer. They rate the *working* range of the AA alkaline as *zero* to 130 degrees F (-18 to 55 C). How cold is your freezer?

Doug Owen

 

[IlluminatingBikr]

I have frozen batteries and used them. They were fine, but I may have just gotten lucky. /ubbthreads/images/graemlins/smile.gif

 

[JSWrightOC]

One thing to consider is that only distilled water freezes at 32F/0C--since it is part of an electrolyte solution, the actual point where significant ice crystals are formed is probably much much lower.

I do have to consider that placing the cells in the freezer instead of the refrigerator may be overkill. Keep in mind that most refrigerators operate at 36F-38F (2C-3C) which is close enough to 32F/0C IMHO. If you really want extreme shelf life, then buy Lithiums (if you're interested in AAs, that is).

The state of charge may have something to do with this as well--I know that a discharged Lead-Acid wet cell will freeze at a higher temperature than a fully-charged one. On that note, since those of us in the Northern Hemisphere are about to enter the winter months...keep your vehicle's battery charged, and if it does go dead and freeze, don't dare charge it!

 

[Doug Owen]

Again, guys, don't worry about the freezer. The guy that makes the battery isn't. He knows some folks leave them in the car in the winter time......

They are guaranteed to work (not just survive storage) at *zero* degrees F.

Not an issue. It just doesn't give you any real advantage either.

Doug Owen

 

[doubleganger]

Not too far off topic, I hope, since I figure batteries in a light not being used could be considered 'shelf' life. I recently decided to change the batteries (alkaline) in the light I keep in my car, just because I figured it was time. I hardly ever used the light but would occasionally cick it on just to make sure it still worked. The D cells were probably about 2 years old but were completely swelled and had leaked to the point that since it wasn't really expensive I just pitched the light. It still worked, though it probably wouldn't have for long. Since I don't remember it getting anywhere near down to zero I assume it was the heat. Anyone have suggestions of about how often to switch out the batteries? How much of an issue would this be for lithiums? I *really* don't want that to happen to a more expensive light.

 

[LightofMine]

I decided to ask Energizer this question. So I send them an email. They sent me an answer right back. Only it was a politician answer. A politician’s answer is when you want a simply yes or no but you get a five minute discussion and they do not answer your question.

They did not say you could not freeze a battery. However, they did not recommend it. They did say if you stored the batteries in a cool dry place the shelf life would be years. They didn’t say how cool or how many years. They said stored in high heat the life could be just a few months. They did not define what high heat was. I would say sitting in a car or truck, in the hot sun with the windows rolled up, would be most people’s definition of high heat. I do keep 3 flashlights in my truck and my wife keeps one in her car.

They did say that temperature had a much greater effect on storage than humidity. That it was more important to keep them cool than dry but cool and dry was preferred.

Then they apologized for me having problems with their batteries. I am not having any problems with their batteries. I just wanted to know if they would last much longer by putting them in the freezer like I use to do my camera film. I don’t do film anymore. I have went 100% digital.

James

 

[Double_A]

Doug-

When I got my answer several years ago(1980's) the answer was a strong NO.

While I acknowledge that things probably have changed, your a braver man than I. I would not go out on the limb as you have and tell people not to worry.

GregR

 

[_mike_]

Interesting questions...batteries and temperature. I wonder if all the warehouses, shipping containers or trucks are climate controlled? I mean, lots of products are transported without regard to temperature and would imagine batteries as well. These products are also left in car trunks,garages, barns, storage sheds, etc, all over the world in obviously many different climates. I wonder if we worry too much about this stuff sometimes.


Mike /ubbthreads/images/graemlins/thinking.gif

 

[Tomas]

[ QUOTE ]
"How many people do you know that keep their house at 68 degrees F all the time? I sure don’t, my house stays at about 75."

[/ QUOTE ]

When I read that just now I glanced over at the digital thermometer in the bookcase next to the TV on the opposite side of the room - it read 68.4F

I do tend to run my home a bit cooler than many people, and often find my bedroom, when I wake up in the morning in cold weather, verging on dropping into the 50's.

Put me in a 75 degree house and I think I'd melt. /ubbthreads/images/graemlins/grin.gif

Take care,

 

[Doug Owen]

[ QUOTE ]
Double_A said:
Doug-

When I got my answer several years ago(1980's) the answer was a strong NO.

While I acknowledge that things probably have changed, your a braver man than I. I would not go out on the limb as you have and tell people not to worry.

GregR

[/ QUOTE ]

Could be brave, but I like to think of it as confidence in the published specs. We were talking Eveready (minus 18 degrees C), checking the competition:

Duracell Alkalines

They seem to think a bit more of their product (minus four F) and even boast:

"Effect of Discharge Load and Temperature
Capable of performance at high discharge rates; typical temperature range: -4°F to 130°F (-20°C to 54°C)."

Then again, I guess they don't think theirs last as long:

"Shelf Life
Up to 85% capacity remaining after 4 years of storage at 70°F (21°C). "

Like I said, a bunch of folks leave their flashlights in their cars overnight all winter long in snow country and don't seem to have any problems.

Makers today seem to say their's no advantage to the (old) practice, but don't seem to have any dire warnings against it either. In fact they seem to say it's no a problem.

Doug Owen

 

[Stanley]

While we're on the topic of batts and temperature, how much do batteries (lithium & alkaline) deteriorate in hotter temperatures? I'm talking about approx 30+ Celcius on average... Are lithiums supposed to be able to perform just as well in the heat just as in the cold?

 

[Double_A]

I stand corrected.

However since there is no advantage I'm not going to bother.

Maybe I'll get a cheap flashlight and some new d cells and freeze them in my freezer, I keep it at -10 F

I'd like to see how well they perform at that temp.

GregR

OK, I put 2 brand new D-cells in one of two old metal body eveready flashlights that I have a few minutes ago (11pm my local time). It went into a ziplock baggies in my freezer. I'll check on it in the morning around 7 am.

Good Results, as of 8 am this morning (9 hrs elapsed time) I removed the flashlight from a -16 F fridge. flashlightsight switch is spotty but output of lamp is about half that of it's twin flashlight. I'm quite surprised and under the circumstances find that quite aceptable. Batteries look fine also, no detectable swelling. I'll let them thaw and see if anything changes, posting if it does.

GregR

 

[dark star]

I've read in several places that putting a charged NiMH cell in the freezer will cut its discharge rate to 1% a month. But you need to thaw it out before using it - it would be faster to just charge up a depleted one. But this freezing would be useful when the power goes out - the cells would be thawed automatically!

 

[gadgetnut]

[ QUOTE ]
dark star said:
I've read in several places that putting a charged NiMH cell in the freezer will cut its discharge rate to 1% a month. But you need to thaw it out before using it...

[/ QUOTE ]Hey, maybe if I thawed them in the microwave, they would not only thaw faster, but it might recharge them too! /ubbthreads/images/graemlins/wink.gif /ubbthreads/images/graemlins/grin.gif



**disclaimer** I'M JUST KIDDING! DO NOT TRY THIS!!

 

[JSWrightOC]

What? huh? /ubbthreads/images/graemlins/smile.gif

(meanwhile, sparks fly in the kitchen, and a deafening explosion is heard)

 

[gadgetnut]

/ubbthreads/images/graemlins/ooo.gif *runs away*

 

[JSWrightOC]

(On Topic)

Regarding NiMH cells in the freezer, it would be interesting to see published specs on this chemistry and it's temperature-to-efficiency slope. I know Energizer specifies basic temperature performance data on NiCd cells, but I see no data on NiMH. It is probably very similar, however.

Stanley,

Self-discharge will increase dramatically with temperature. Unfortuniately Energizer does not list service maintenence at temperatures higher than 40C (104F) for their alkalines, but I'm sure you can extrapolate the data. As for lithium iron disulfide (~1.5V) and lithium manganese dioxide (~3V) they list a performance at 70C (158F, ouch!) and it looks like there is a dramatic dropoff in the slope somewhere between 40 and 70 (probably near 60C, the rated maximum of Lithium chemistry cells)...unless alkaline chemistry cells exhibit a similar "knee" then it is theoretically possible that at extremely high temperatures alkaline cells may surpass lithium primary cells in longevity. I seriously doubt you would see temperatures *that* high in your car, however. /ubbthreads/images/graemlins/smile.gif