If the phone's battery lay for a year, did it shorten its life?

Question

Batteries

After 3 months of operation, the phone broke down, but the battery (I didn’t have time to look - Li-Ion or Li-Pol) remained in it. So the year went. Has the battery capacity dipped a lot, should it be used in another phone?
UPD: And is it likely that after a while it will swell or is there any such thing? It's just that suddenly half a day is only left to test the battery and decide whether to leave it in your phone and give your battery away.

Answer 1

Yes, she sank. Lithium ages over the years.
How much - try.

Answer 2

It seems like if the battery was charged and slowly discharged, then there was nothing good for it in such storage.