The tech giant are locking their batteries so that a message is shown if a battery is fitted that isn't one of their own and now they have issued a statement on why they added the update in 2018.
In a statement to The Verge, Apple said: "Last year we introduced a new feature to notify customers if we were unable to verify that a new, genuine battery was installed by a certified technician following Apple repair processes.
"This information is there to help protect our customers from damaged, poor quality, or used batteries which can lead to safety or performance issues."
The message appears when the power pack needs servicing, regardless of whether it is an Apple battery or not, on iOS 12 and iOS 13 beta.
Under the Battery Health menu, a Service message will be shown, reading "Important Battery Message".
It warns: "Unable to verify this iPhone has a genuine Apple battery. Health information not available for this battery."
The message replaces the standard battery percentage icon on current iPhones.