Apple has confirmed the battery capacity of the new iPhone Duo, iPhone 18 Pro, and iPhone 18 Pro Max. In a regulatory filing in Europe, Apple revealed the iPhone Duo’s battery specifications—details the company does not typically publish on its official product pages.
The exact battery capacity was confirmed through official documentation published in the European Product Registry for Energy Labelling (EPREL) database. Ahead of customer deliveries and broad retail availability, Apple uploaded the required EU energy labels for its first foldable smartphone.
Under EU energy labeling rules, manufacturers must disclose rated battery capacity, expected endurance cycles, and longevity metrics. The disclosure confirmed earlier component leaks indicating a split dual-cell battery architecture designed to fit the foldable chassis.
According to Apple’s filing, the iPhone Duo features a total rated capacity of 4,883 mAh, distributed across a dual-cell structure consisting of a 2,962 mAh primary cell and a 1,921 mAh secondary cell. Because the iPhone Duo is an eSIM-only model worldwide without a physical SIM tray taking up internal space, this 4,883 mAh capacity applies uniformly across all regional variants. The official EU energy label rates the device for an endurance of 51 hours and 30 minutes per charge cycle under standardized test conditions, with a battery lifespan rated to retain at least 80% of its original capacity after 1,000 full charge cycles.
In comparison, the iPhone Duo features a larger battery than the iPhone 18 Pro (4,288 mAh), but significantly smaller capacity than the iPhone 18 Pro Max (5,567 mAh).
Source: Macrumors
