Apple may have left another clue about its future iPhone hardware in iOS 27 Developer Beta 4. New Battery Health strings discovered in the latest beta refer to multiple internal batteries instead of the single battery found in every current iPhone model.
The strings were first spotted by Macworld and later confirmed by MacRumors, suggesting Apple is preparing iOS to support an iPhone with more than one internal battery.
Battery Health messages now reference multiple batteries
Current iPhone models display Battery Health messages that refer to a single battery. In iOS 27 Developer Beta 4, however, Apple has updated the wording to use plural references, including messages such as:
- “The batteries in this iPhone are performing as expected.”
- “The health of the batteries in this iPhone has significantly degraded.”
Another newly discovered string states that one of the batteries could not be verified as a genuine Apple battery. This suggests iOS is being prepared to identify and monitor the condition of individual battery cells rather than treating the device as having a single battery.
Apple has not explained the reason for these new strings, but their presence strongly suggests the company is laying the software groundwork for future iPhone hardware that includes multiple internal batteries.
Foldable iPhone is the most likely candidate
According to Macworld, the new Battery Health strings are most likely intended for Apple’s long-rumored foldable iPhone, although Apple has not confirmed which device they are designed for.
Previous reports claim Apple’s first foldable iPhone will feature two separate battery cells with capacities of 1,921mAh and 2,962mAh, combining for a total battery capacity of approximately 4,883mAh.
A dual-battery design is common among book-style foldable smartphones because each half of the device typically houses its own battery cell. Apple is widely expected to adopt a similar internal layout for its foldable iPhone.
The updated Battery Health wording also suggests iOS may eventually display the condition of each battery separately, potentially giving users more detailed information about battery health and servicing. Whether this also changes how future foldable iPhones are repaired or how battery replacements are handled remains unknown.
If current rumors prove accurate, Apple’s first foldable iPhone could debut alongside the iPhone 18 Pro lineup later this September.
Would you like Apple to make individual battery cells easier to replace if it launches a foldable iPhone? Let us know in the comments below.



