Freezing Batteries??

[Robocop]

I have a friend who I was visiting recently and we began talking about battery life.He informed me that he keeps all his alkaline batteries in the freezer until he is ready to use them.He swears this makes them last longer and I am now wondering the same thing.I always thought cold was the enemy to alkaline batteries as they do not perform well in freezing temps.He says that the cold temps keeps the chemicals more stable and will hold the battery for longer periods until ready for use....I am asking this as I am fast obtaining alot of extra alkaline cells and am finding it hard to use them fast enough.If there is some better method of storing them I would like to know it.
So basically does freezing batteries before use work or is my friend crazy?

 

[PhotonBoy]

From what I remember about my chemistry, for each 10 degree Celsius drop in temperature, the chemical activity in a cell decreases by half (approximately). So if you drop the temperature of a cell from 20C (room temperature), to about -10C, the chemical activity in the cell declines to about an eighth, prolonging its life. I would call this 'chilling' the cell, rather than 'freezing' it, since I'm not sure there's a lot of water in an alkaline.

 

[turbodog]

This test had been done in a lab. Yes, it works. No, it is not worth the hassle. You're much better (cheaper) off by getting a good deal when you buy them. I only keep about 2 months worth on hand myself.

 

[modamag]

Here are some hard numbers which might help depending on your environment.

Alkaline self discharge
- 2%/yr @ 70F
- 5%/yr @ 85F
- 25%/yr @ 100F

NiMH self discharge
- 30%/mo @70F
- 50%/mo @85F
- 70%/mo @100F

NiCd self discharge
- 20%/mo @70F
- 35%/mo @85F
- 50%/mo @100F

The NiCd and NiMH capacity decreases 10% in the first 24h, then declines to about 10% every 30 days thereafter.

If you were gonna freeze them let them thaw back to room temp prior to using it.

Personally it's not worth the hassle, plus they are taking up beer space /ubbthreads/images/graemlins/drunk.gif

 

[Sub_Umbra]

ensig,

My NiMH cells retain a charge much better than those figures would indicate.

About six montha ago I bought a bunch of POWERIZERS in AA and D and they hold their power very well indeed. I just lit a Jack-o-lantern with a Hyper-Blaster with POWERIZERS that had been sitting just slightly above 80 F for three months since charging and I appeared to get about 70% of what I got out of freshly charged cells from the same batch. I have also noticed better retention from another brand I bought 3 years ago in other devices.

The only explanation I can come up with is that the manufactureing process for NiMH cells has improved since those figures were published.

 

[HarryN]

You are right ensig, today's alkalines are very good at retaining charge. 10 years ago, those numbers were quite a bit higher.

My garage, which is where my batteries are usually stored, can hit 110 F every day in the summer, so the discharge rate is significant. I am saved only by fact that I hardly ever have a battery that is more than a few months old.

 

[andrewwynn]

the studies i've seen show it's not worth the effort to cool your batteries... especially with alkaline batteries that have dates stamped on them and have 4+ yr shelf lifes... the more interesting study i've seen was with LiON batteries that showed that the capacity retention is higher when the batteries are stored at lower CHARGE vs lower TEMP... i.e. 40% charge is ideal for storage retention.

In any event.. i wouldn't keep a battery in a cold location specifically but i would avoid a hot location.. hot is not good for any battery chemistry.

-awr

 

[cobb]

Ive heard of folks doing this for film too.

 

[STEVENT6]

What about self discharge for rechargeable alkaline? I left a mag 4D in the trunk of my car from about jan to aug this year. When I took it out I was curious so I turned it on for about 5-10 minutes before recharging the batteries, it seemed quite bright. I've had the batteries since 1999 and may have recharged them about 10 times. I live in PA hot in summer, cold in winter. The batteries were never abused, charged every so many months after some use. Either sitting in house or car. Is this normal for rechargeable alkalines? If it is, wouldn't it be about the only advantage for using them? As I bought them before I knew about this site.

 

[Lynx_Arc]

I would probably consider refrigerating batteries if you only had a place to store them in that was hot in excess of 90-100 degrees all the time but most people have places to store them where they live in climate controlled areas.

 

[BobVA]

I usually keep my in the frig. I've got the space and I figured that it "can't hurt".

I didn't have much luck with the freezer, though. Some AAA's I stored in there leaked pretty badly (but the goop was a tidy solid /ubbthreads/images/graemlins/smile.gif)

 

[fivemega]

Don't freeze used alkalines.
Seal them (to prevent moisture) before freezing.
Let them back to room temperature before using.

 

[Lynx_Arc]

most likely putting them in the vegetable crisper in a ziplock bag with a dessicant pack would be more than adequate. I don't think freezing them would really gain you much more storage life and thawing them out is a lot of trouble when you need them.

 

[mattheww50]

Two comments. Keeping them in the refrigerator is probably more than adequte, reducing the temperature from 25C to 5C should quadruple the shelf life, so it goes from 2-3 years to about a decade. If you aren't planning to use them within a decade, you probably shouldn't have bought them in the first place!

Freezing has its hazards. I haven't seen it on larger batteries, but on button cells, I have seen the ice crystals that form damage the elastomer seals so the battery may leak in use. If you don't freeze the cells, that cannot happen.

 

[Robocop]

Well I guess my friend was partially correct here.I was thinking cold hurt the alkalines as far as performance goes...Ok let me see if I got this correct here...Cooler temps will increase the shelf life of an alkaline however they must be allowed to warm to room temp before use in order to get the most from them...is this correct?
I have read here that lithiums perform much better in freezing temps.This is meaning when actually used in freezing temps and not stored correct?...I have bought many lights over the last year and many came with batteries installed.Before I knew it I had a big pile of AA and AAA sizes.I really dont like to store the alkalines in my lights so I keep them in a box seperate.I often find myself hoping for a power outage simply so I can find an excuse to use up my stockpile of batteries..hehe

 

[mapson]

I'd like to see the numbers for Li-ons and Lithiums.

[ QUOTE ]
ensig said:
Here are some hard numbers which might help depending on your environment.

Alkaline self discharge
- 2%/yr @ 70F
- 5%/yr @ 85F
- 25%/yr @ 100F

NiMH self discharge
- 30%/mo @70F
- 50%/mo @85F
- 70%/mo @100F

NiCd self discharge
- 20%/mo @70F
- 35%/mo @85F
- 50%/mo @100F

The NiCd and NiMH capacity decreases 10% in the first 24h, then declines to about 10% every 30 days thereafter.

If you were gonna freeze them let them thaw back to room temp prior to using it.

Personally it's not worth the hassle, plus they are taking up beer space /ubbthreads/images/graemlins/drunk.gif

[/ QUOTE ]

 

[PhotonBoy]

The rate of decrease in chemical activity with temperature reduction is independent of the chemicals used, so the rates should be more or less the same.

 

[Ray_of_Light]

The whole thermodinamics of batteries is optimized, by design, at 20 degree Celsius, for use and storage.
Freezing batteries, in many cases, can do more harm than relief.
The crimp seal of water-based electrolyte batteries is also mechanically stresses by the freezing, in many cases destroying them.

Anthony

 

[PhotonBoy]

Knowing that salt on roads melts ice, it would be interesting to know at what temperature the electrolyte in an alkaline actually solidifies/freezes.