Dipende da come vengono mantenute le batterie poiché le batterie ai polimeri agli ioni di litio devono essere usate e ricaricate regolarmente . Ci sarà sicuramente una riduzione della capacità con il passare del tempo, indipendentemente dal fatto che le batterie siano regolarmente usate / caricate o meno.
Da Battery University - La batteria ideale è agli ioni di litio? (enfasi mia):
Aging is a concern with most lithium-ion batteries and many manufacturers remain silent about this issue. Some capacity deterioration is noticeable after one year, whether the battery is in use or not. The battery frequently fails after two or three years. It should be noted that other chemistries also have age-related degenerative effects. This is especially true for nickel-metal-hydride if exposed to high ambient temperatures. At the same time, lithium-ion packs are known to have served for five years in some applications.
Manufacturers are constantly improving lithium-ion. New and enhanced chemical combinations are introduced every six months or so. With such rapid progress, it is difficult to assess how well the revised battery will age.
Riferimenti: Apple - Batterie agli ioni di litio
Battery University