Li-Ion cell with partial charge

wptski

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Jan 18, 2004
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Warren, MI
Too low of a LVC will damage a Li-Ion cell. Overcharging will damage a Li-Ion cell too.

New cells are shipped with a partial charge because a Li-Ion cell fully charged suffers some sort-of damage when left for a period of time.

The question is, how long of time in a fully charged state casues damage to the cell? Anybody see anything written about the lenght of time?
 

SilverFox

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Jan 19, 2003
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Bellingham WA
Hello Bill,

Battery University found that cells stored at 100% full charge at room temperature lost 20% of their total capacity in one year. This lost capacity can not be recovered through cycling.

If this loss is linear (a big IF), that works out to about 1.7% per month.

Tom
 

cy

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Dec 20, 2003
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thanks, I've always wondered why mgf recommend storing at 50% charge
 

wptski

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Jan 18, 2004
Messages
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Location
Warren, MI
[ QUOTE ]
SilverFox said:
Hello Bill,

Battery University found that cells stored at 100% full charge at room temperature lost 20% of their total capacity in one year. This lost capacity can not be recovered through cycling.

If this loss is linear (a big IF), that works out to about 1.7% per month.

Tom

[/ QUOTE ]
Tom:

Thanks! Well, just still looking for the reason one of my Pila 168S capacity is only 50mAh and that isn't it! /ubbthreads/images/graemlins/icon23.gif

Still looks like a low LVC is the killer!
 
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