After update my iPhone bettery health 2 percent low why 😳

Your iPhone's battery health gets calibrated after an update (and also at other intervals). During the most recent battery health calibration, the software determined that it dropped by 2%.

The battery health of your iPhone is now at 79% and the battery should therefore be replaced. Apple recommends that the iPhone battery should be replaced if the battery health capacity reaches 80% or lower to prevent performance related issues.

Axel F.

sujoy ~ The long process of applying an iOS update to an old iPhone with a weak battery can be the proverbial "straw that broke the camel's back." ...So have the aging battery replaced and all will be well:

iPhone Battery & Power Repair

About genuine iPhone batteries

Repair Provider Verification

(Articles found by searching Apple's Knowledge Base.)

õ¿õ¬