According to a screenshot shared by an X user named Tech_Reve, battery cycle information can be seen on iPhone 15 models by going to Settings > General > About.
BESIDE THE NUMBER OF BATTERY CYCLES…
According to MacRumors, there is a new “Battery” section towards the bottom of the page. Along with the battery cycle count, the manufacturing date and first use date are also listed.
Previous methods to check iPhone’s battery cycle count consisted of using third-party apps or some methods like copying and pasting the analytics into Notes and searching for “last_value_CycleCount”.