My iPhone 13 Pro Max battery has started draining very fast. drops by 10% every hour. I don't know if the last update to 17.5.1 has caused this. Battery was lasting fine until the last month. Ive added no new apps or changed any services.
iPhone 13 Pro Max, iOS 17
What is important, is the battery's Maximum Capacity.
Tap Settings > Battery > Battery Health & Charging
What is the current Maximum Capacity?
Approximately, how old is your phone?
Every single iOS upgrade since I started posting here 20 years ago has resulted in complaints of battery drain. I suspect if you add more features then there's more drain. That's more or less the way it goes. Changes in software such as upgrades may introduce new features which may add to power drain and heat generation. Check Settings > Battery feature to see if there are apps or services running that use a lot of power. If there are, decide if you need them running all the time, can turn off a service when an app is in the background, or disable the feature completely. Read this support article to learn about the battery health feature. —> iPhone Battery and Performance - Apple Support
Refer to this post for good tips on reducing battery use on your device --> iPhone 14 pro battery health reduced to 9… - Apple Community
Addendum to #11. Use 4G/LTE instead of 5G. Use 5G with your iPad - Apple Support
Here is a related post in the context of device heating. --> iphone pho max 14 phone gets hot - Apple Community
iPhone 13 Pro Max battery starting draining fast
