I wouldn’t consider that entirely true, alot of variables that can effect the shelf life of li-ions.
Temperature subjected to (A major factor), number of cycles on the cell, the discharge current their subjected to, the ending voltage of the discharge, the cut off voltage their charged too, how quickly their charged once discharged.
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My cell phone batteries usually last around two years. Its charged and used daily in varying temperatures, I work outside and carry it daily in the cold winter and hot summer. That’s about all I ever get out of a cell phone battery.
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On the other hand I have Panasonic NCR18650 2900mah cells from this thread. FYI - some 'new' Fujitsu laptop batteries
With a date code of 9926, made 2009 in September. This being close to the 5th year.
These cells where never used until last year, when I purchased them. From the test I have done and others, they seem as though they just rolled of the assembly line. I store mine at around 67°F and the two I set aside for testing purposes have lost very little voltage after 10 months of being fully charged. After 2 more months (making a year) I will update ohaya’s thread with resting voltage and a tested discharge capacity.