Shelf Life - what does it means?

LA OZ

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When manufacturer states the battery has 10 years shelf life, what does that mean? Does it means - takes 10 years to loss 50% capacity or 100% etc?
 

soffiler

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When manufacturer states the battery has 10 years shelf life, what does that mean? Does it means - takes 10 years to loss 50% capacity or 100% etc?

The Energizer data sheet for L91 (AA format, lithium/iron disulfide chemistry, 1.5volts) says 15 years stored at 21C to 90% of rated capacity. Oddly, the Energizer datasheet for 123 (lithium/manganese dioxide chemistry, 3.0 volts) makes no mention of shelf life. (They may deal with it elsewhere in their literature.)
 

LuxLuthor

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When manufacturer states the battery has 10 years shelf life, what does that mean? Does it means - takes 10 years to loss 50% capacity or 100% etc?

I doubt there is an industry wide standard that they all follow. Some may say 10 year shelf life that means 50% of original, another 90%. Probably the Gold Standard is Surefires 123a 10 year shelf life...but even they don't say what that specifically means in terms of % of original mAh, nor did their tech support line have an answer when I called just now.
 

jsr

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Lithiums have pretty low self discharge. After 10yrs, they still should have 80+% capacity. I was once told by SilverFox that the shelf life refers more to the seals and not the remaining capacity.
 

LA OZ

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This is all meaningless when there is no proper definition. Shelf life term got throwing around and no body know what it means. :(

Silverfox, where are you?
 

SilverFox

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Hello LA OZ,

I think you have received some very good answers so far...

Under ideal storage conditions (60 F and 50% RH) you can expect Alkaline cells to have around 80% of their initial capacity at their expiration date, and Lithium cells should have around 90% of their initial capacity.

Heat things up and you end up with less capacity, cool things down and your shelf life increases.

Tom
 
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