[DigitalToday reporter Jinju Hong (홍진주)] A leak has put the total battery capacity of Apple’s foldable iPhone, widely referred to as the “iPhone Ultra”, at 4,883 mAh. The claim is based on documents Apple’s battery supplier recently submitted to a regulator.

NineToFiveMac reported on July 10 that leaker Digital Chat Station said in a Weibo post that two batteries were listed at 1,921 mAh and 2,962 mAh. Combined, they total 4,883 mAh. If correct, the figure increases the likelihood that the iPhone Ultra adopts a dual-cell battery structure using two cells, like foldable phones from Samsung Electronics and Google.

Battery structure is directly tied to foldable device design. Because internal space differs from conventional bar-type smartphones due to the folding display, splitting the battery into two parts is widely used. The leak also suggests the iPhone Ultra could have hardware different from existing iPhones.

Comparisons were also provided. The Samsung Galaxy Z Fold7 was introduced as having a total 4,400 mAh battery, while the Google Pixel 10 Pro Fold was introduced as having a 5,015 mAh battery. The previous generation Pixel 9 Pro Fold had 4,650 mAh. The iPhone Ultra’s 4,883 mAh sits between them.

The leak also revealed part of the battery picture for the new iPhone lineup expected to be unveiled in September. The iPhone 18 Pro was cited at 4,288 mAh for the eSIM model and 4,056 mAh for the physical SIM model. The iPhone 18 Pro Max was put at 5,567 mAh for the eSIM model and 5,391 mAh for the physical SIM model. The increases versus the iPhone 17 Pro, cited as a comparison baseline, were 36 mAh or 68 mAh for the iPhone 18 Pro and 479 mAh or 568 mAh for the iPhone 18 Pro Max.

Still, it is difficult to draw conclusions about actual usage time based on battery capacity alone. The outlet noted that battery capacity “tells only a small part of the story”. It said that in cases where the form factor changes significantly, such as a foldable iPhone, many variables can work together, including display size and driving method, and software optimisation.

It also remains that actual battery life and power efficiency cannot be confirmed until Apple’s official announcement. The outlet said that “many variables come into play” in iPhone battery life and reported that even for the iPhone Ultra, “we will have to wait for the official announcement in September”.

As a result, the leak is being taken as a gauge of battery capacity and the direction of internal design. If a September unveiling materialises, the key points to watch will be what battery strategy Apple chose in the foldable market and whether it secured competitive usage time versus Samsung and Google.