As promised, Apple has included a new screen in the iOS 11.3 beta 2 settings called Battery Health (Beta) available on all iPhones since iPhone 6. This view includes information about the maximum capacity of the battery in the device, and describes whether the battery has degraded to the point where it can no longer offer peak performance.
Currently, performance management may be enabled by the system on iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7 and iPhone 7 Plus.
Accessing Battery Health
With iOS 11.3 beta 2 installed, open Settings -> Battery -> Battery Health.
Check more tips on this page:http://www.3u.com/tutorial/articles/5686/how-to-check-battery-health-in-ios-11-3-beta
Battery Health (Beta) available on all iPhones since iPhone 6
Moderators: Lily Lee, jc_3u, Moderators