My iPhone 13 pro max battery has been dropping rapidly
Why my iPhone battery drops rapidly
Question marked as
Your battery may be at the end of its life.
Batteries degrade over time with usage due to chemical aging, that's just how they work.
You can expect about a 1% drop per month with average use on an iPhone.
Apple recommends replacing it when it reaches 80%. To check your battery health, go to Settings > Battery > Battery Health.
iPhone Battery Replacement.
iPhone Battery Repair & Replacement - Apple Support
About Lithium Ion Batteries
iPhone Battery and Performance - Apple Support (IN)
Here are some tips on maximizing battery life.
Batteries - Maximizing Performance - Apple