Apple’s first foldable iPhone is shaping up to be one of the company’s most ambitious releases, but the latest leak suggests a notable compromise. The device, widely referred to as iPhone Ultra, is said to carry a smaller battery than the iPhone 18 Pro Max despite having to support two displays.
That detail comes from Digital Chat Station on Weibo, which says Apple has registered two new battery cells for the device. Together, they reportedly add up to 4,883 mAh, a capacity that looks modest for a premium foldable built around two screens.
A Capacity That Trails Expectations
The reported 4,883 mAh figure sits below earlier expectations and also below the iPhone 18 Pro Max, which is projected to land between 5,235 mAh and 5,425 mAh depending on SIM configuration. For a device expected to sit at the top end of Apple’s lineup, that gap is hard to ignore.
Compared with rivals in the foldable market, the number is not an outright lead either. The Galaxy Z Fold 7 is said to come with a 4,400 mAh battery, while the Pixel 10 Pro Fold is listed at 5,015 mAh.
| Device | Battery Capacity | Note |
|---|---|---|
| iPhone Ultra | 4,883 mAh | Dual-cell design for two screens |
| iPhone 18 Pro Max | 5,235–5,425 mAh | Varies by SIM configuration |
| Galaxy Z Fold 7 | 4,400 mAh | Foldable competitor |
| Pixel 10 Pro Fold | 5,015 mAh | Foldable competitor |
Digital Chat Station also suggests Apple may market the battery as roughly 5,000 mAh. That kind of rounding would not be unusual, as Apple has often used marketing figures that differ slightly from technical capacity.
Why The Number May Stay Lower Than Expected
A foldable design leaves far less room inside the chassis. The iPhone Ultra has to accommodate a hinge mechanism, a thicker flexible display layer, protective frame structure, and careful weight balance when the device is opened or closed.
Those components leave less space for the battery, which helps explain why a larger capacity may not be possible. Even if Apple is using a high-density battery, the raw mAh total still appears to be constrained by the form factor.
The trade-off looks deliberate rather than accidental. Apple appears to be prioritizing thinness, structural durability, and balance over chasing the highest battery figure on paper.
How It Stacks Up Against iPhone 18 Pro Max
The contrast becomes sharper when the iPhone Ultra is compared with the iPhone 18 Pro Max. The foldable is more expensive and more complex, yet it is not expected to carry the larger battery.
| Feature | iPhone Ultra | iPhone 18 Pro Max |
|---|---|---|
| Device type | Two-screen foldable phone | Conventional slab phone |
| Display | 7.8-inch inner + 5.5-inch outer | About 6.9 inches |
| Battery capacity | 4,883 mAh | 5,235–5,425 mAh |
| Chipset | A20 Bionic | A20 Bionic |
| Operating system | iOS 19 | iOS 19 |
| Estimated price | $1,999–$2,199 | $1,199–$1,399 |
Apple has long relied on software efficiency and tight hardware integration rather than massive battery cells. With A20 Bionic and iOS 19, the company may still be able to offset some of the capacity gap in real-world use.
But a foldable that powers two screens at once introduces a new challenge for the iPhone line. That makes battery endurance one of the most closely watched questions around the device.
A Middle Position In The Foldable Market
Apple’s approach appears to land somewhere between the biggest battery leaders and the lighter competitors. The company is not chasing the level reportedly seen in the Huawei Mate X6, which is said to be around 5,200 mAh, but it is also not far from the Samsung Galaxy Z Fold 7.
That balance fits Apple’s usual strategy of focusing on design, performance, and user experience. In this case, the cost of entering the foldable category seems to be a battery compromise.
Digital Chat Station says the device has already entered mass production and remains on track to launch alongside the iPhone 18 Pro and Pro Max in September 2025. If Apple’s internal testing has approved the design, the 4,883 mAh battery may still be considered sufficient for a full day of use.
Even so, for a premium foldable expected to juggle two displays, the leak points to a clear trade-off that could shape how the iPhone Ultra is judged before it even reaches the market.
