Low battery health
Hi, I have an iPhone 12 mini, it’s 9 months old but the battery health is already at 89%, I don’t know why it’s dropping so fast.
I try to charge it once a day
iPhone 12 mini
From these boards, most users see a reduction in battery health of 1-2 percent per month. So, you're right about there. If it drops below 80 percent in the first year, have Apple replace your battery.