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Of course, assuming you wrap it in a tight plastic bag to avoid humidity.

I have a laptop battery at my office that's not currently in use, and also won't be used at least for the next several months. I know that Lithium-ion batteries degrade faster at higher temperatures. enter image description here
And if this image (kindly stolen from a Lifehacker article) is to be believed, even at room temperature (25C, 77F) the estimated loss is around twice the loss at 0C (32F).

In the last couple of weeks, the temperature here at the office has been approaching the 36C (100F) and rising. So it occurred to me it might be better to store it in the freezer (or perhaps the refrigerator) to slow the aging effect. Is that correct and safe?

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Take a look at this. – soandos Jan 12 '12 at 14:10
I guess you will have to chuck one in the freezer and update us with the results later. It also makes me wonder is it really economical? – Shekhar Jan 12 '12 at 14:34
How much extra power could it possible take to add one more thing into the freezer/refrigerator? – soandos Jan 12 '12 at 14:57
@soandos: The three factors that determine freezer efficiency are its isolation, how often you open the door, and how often you add new warm content. It doesn't matter how long you store something. – MSalters Jan 13 '12 at 12:44
up vote 8 down vote accepted

Going off your Lifehacker article, a refrigerator will be fine, as it is within the temperature range that is mentioned in the chart, and will probably help some.

With regard to the freezer, I have been unable to find a definitive answer, but I would mention a few points:

  1. There is no water in a lithium ion battery, so it is highly unlikely that anything interesting will occur at that temperature
  2. There is very little (comparative benefit) that you can get. Even if you can halve the loss rate by going to whatever your freezer goes to, it is no-where near as big a difference as going from room temperature to a refrigerator (close to 0 C).

Note: While even if in general there is no issue with putting a lithium battery in the freezer, since the amount of charge that it can hold is reduced at very low temperatures, it should not be fully charged when you put it in the freezer. Thank you @BruceConner for pointing it out.

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With regards to 1. I looked into @soandos' link and they mention something that makes sense. The maximum capacity of a Li-ion battery is temporarily decreased while at very low temperatures. So, if the battery is fully charged and you reduce its temperature to freezer levels, it will become overcharged, and that could cause damage. – Malabarba Jan 12 '12 at 15:15
Good point, will update. – soandos Jan 12 '12 at 15:19
No advantage to freezer, many disadvantages. the li-ion batteries can handle -20*C easily, but most freezers do not just hold the temps. they have defrost cycles. So while in the fridge part they will stay within a few degrees here and there (good). In the freezer part of a refer the temps will bounce around a lot when it defrosts. Expansion and contraction of disimilar materials via huge temps swings? The problem of condensation (on removal), which is reduced by sealing and bringing back up to room temps. Side notes: li-ion can be damaged by charging in extreeme low temps. – Psycogeek Jan 13 '12 at 9:47

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