iPhone Ultra Battery: Everything Leaked So Far

Here is a comprehensive, fact-checked breakdown based on the latest available leaks and regulatory filings.

iPhone Ultra (Foldable) Battery — What the Leaks Say

The latest credible leakers, including Fixed Focus Digital on Weibo and Front Page Tech, point to a battery capacity between 5,500 mAh and 5,800 mAh, with multiple sources converging around ~5,800 mAh . This would make it the largest battery Apple has ever put in an iPhone, under the "iPhone Ultra" or "iPhone Fold" branding .

It is important to note that these are still pre-release leaks. Apple has not officially confirmed any specifications for its foldable iPhone.

Battery Comparison: iPhone Ultra vs. Galaxy Z Fold7 vs. iPhone 18 Pro Max

Device	Battery Capacity	Source
iPhone Ultra (leaked)	~5,500–5,800 mAh
Samsung Galaxy Z Fold7	4,400 mAh (official)
iPhone 18 Pro Max (3C filing)	5,391 mAh (China) / 5,567 mAh (US)

• The iPhone Ultra's rumored battery would be 25–32% larger than the Galaxy Z Fold7's 4,400 mAh cell and slightly larger or comparable to the iPhone 18 Pro Max's US variant (5,567 mAh) .
• The Galaxy Z Fold7's 4,400 mAh is a carryover from the Z Fold6, unchanged for the 2025 generation .

iPhone 18 Pro & Pro Max — Battery Specifications from Regulatory Filings

New 3C certification filings in China, leaked by the reliable Weibo account Digital Chat Station, have revealed battery capacities for both models months before their expected September launch :

Model	China Capacity	US/International Capacity
iPhone 18 Pro	4,056 mAh	4,288 mAh
iPhone 18 Pro Max	5,391 mAh	5,567 mAh

• The iPhone 18 Pro sees only a modest increase over the iPhone 17 Pro .
• The iPhone 18 Pro Max gets the big jump: an ~11.8% increase in the China variant (4,823 mAh to 5,391 mAh) and a ~9.4% increase in the US variant (5,088 mAh to 5,567 mAh) compared to the iPhone 17 Pro Max . This is the largest single-generation Pro Max battery gain in years.

Engineering Constraints — Why the Foldable Battery Isn't Even Larger

Several factors explain why the Ultra's battery isn't even bigger :

• Ultra-thin profile: Leaks suggest the iPhone Ultra targets a ~4.5 mm thickness when unfolded — one of the thinnest foldables on the market . This dramatically limits the internal Z-height available for battery cells.
• Dual-cell constraint: Foldables typically require two physically separate battery cells (one on each side of the hinge) wired in series . This reduces packing efficiency compared to a single slab-form cell of the same total volume.
• Hinge and display mechanisms: The folding screen, hinge assembly, and support structures consume internal volume that a slab phone like the Pro Max can dedicate entirely to battery.
• Structural rigidity: Apple reportedly reinforced the frame and hinge for durability, further compressing the battery compartment .

The takeaway: ~5,800 mAh in a ~4.5 mm foldable is already an impressive engineering achievement.

Launch Timeline, Pricing & Supply Constraints

Announcement date: Most reliable sources — including Bloomberg's Mark Gurman and multiple supply chain reports — point to a September 2026 reveal, likely September 8 or 9, alongside the iPhone 18 Pro and Pro Max .

Availability:

• The iPhone 18 Pro and Pro Max are expected to ship in late September following a standard pre-order timeline.
• The iPhone Ultra faces significant supply constraints. Analyst Ming-Chi Kuo warns that lower-than-expected production yields could severely limit initial units. He predicts the device "could sell out immediately after pre-orders open, with delivery lead times quickly stretching to 4–6 weeks or longer" .
• Some reports speculate a broader ship date could slip into October–November, similar to the iPhone X launch pattern .
• However, multiple supply chain sources pushed back in July 2026, stating that mass production is on schedule for a joint September launch with no postponements .

Pricing:

• Widely estimated at $2,300–$2,500 starting price . CNET and other outlets cite a floor of $2,000+ .
• Higher storage tiers (up to 1 TB) could push past $2,500 .

Bottom line on availability: The Ultra will almost certainly be a very constrained launch — extremely difficult to buy at first, with long lead times expected until 2027 .