New documents from a Chinese certification authority have revealed the expected battery capacities of the upcoming iPhone 18 Pro and iPhone 18 Pro Max. The most notable increase goes to the Pro Max — while the smaller Pro model gained very little. Let’s break down what this means for real-world battery life, how much the batteries will differ between the senior and junior versions, and what the differences are compared to the iPhone 17 Pro and 17 Pro Max.
The battery in the iPhone 18 Pro Max will indeed be huge
Battery Capacity in iPhone 18 Pro and 18 Pro Max
The data was spotted in the Chinese C3 certification database by a well-known insider under the nickname Digital Chat Station. This is a leak, not official Apple information — the devices in the documents are not directly named iPhone 18 Pro and Pro Max, but they very likely correspond to these models.
According to these documents, the iPhone 18 Pro received 4,056 mAh in the Chinese version and 4,288 mAh in the American version. For comparison, the iPhone 17 Pro had 3,988 and 4,252 mAh respectively. So the increase is symbolic — only 68 and 36 mAh.
The iPhone 18 Pro Max looks more interesting: 5,391 mAh in China and 5,567 mAh in the US compared to 4,823 and 5,088 mAh in the previous generation. That’s an increase of nearly 500 mAh — a significant step forward specifically for the senior model.
The senior Pro Max model gets nearly 500 mAh added to its capacity
How Chinese and American iPhone 18 Pro Models Differ
Many people are confused by the different numbers for the US and other countries. The reason is simple and technical: American iPhones don’t have a SIM card tray — they work exclusively on eSIM (built-in electronic SIM) starting with the iPhone 14 lineup.
Without a physical tray inside the body, a bit of space is freed up, and Apple uses it for a slightly larger battery. That’s why the US version in every generation gets more milliamp-hours than the model with a regular SIM slot.
For Russian users, this means that the actual capacity will be closer to the Chinese figures, not the record-setting American ones — when it comes to versions with a physical SIM.
How Much Will iPhone 18 Pro Max Battery Life Improve
Increased capacity alone doesn’t guarantee longer battery life. But here there’s an important additional factor. Digital Chat Station notes that the 5,391 mAh battery paired with the new A20 Pro chip, manufactured using a more efficient 2-nanometer process, could deliver a noticeable improvement in battery life.
Real-world battery life will only be revealed by independent tests after release
The logic is that a thinner manufacturing process usually means lower power consumption at the same performance level. Combined with a large battery, the iPhone 18 Pro Max could become noticeably more enduring than its predecessor. But this is an insider’s prediction, not test results — real-world battery life will only be shown in reviews after release.
The smaller iPhone 18 Pro model, with its increase of just a few dozen mAh, is unlikely to impress with its battery life. Here, everything will depend primarily on the efficiency of the new chip rather than the battery size.
What Else Is Known About iPhone 18 Pro
Beyond the battery, there are several rumors circulating about other changes in the lineup. According to available information, the iPhone 18 Pro may feature:
- a smaller Dynamic Island — the area around the front camera
- a main camera with variable aperture (adjustable lens opening for controlling depth of field and light)
- the new A20 Pro chip on a 2-nanometer process
- a Qualcomm modem for the American market and Apple’s own C2 modem outside of it
All of these points are still rumors and leaks, not confirmed specifications. The documents also indicate that all four battery models are certified through May–June 2031, and the maximum charging voltage is 4.520 V.
The iPhone 18 Pro and Pro Max are expected to launch in September — presumably alongside the first foldable iPhone from Apple. Their presentation date is reportedly set for September 9.
Is It Worth Waiting for iPhone 18 Pro for the Battery
If battery life is your main consideration, it mostly makes sense to wait for the iPhone 18 Pro Max: it’s the one getting a significant capacity increase and the potential benefit from an efficient chip. The regular iPhone 18 Pro is nearly identical to the current model in terms of battery, so iPhone 17 Pro owners shouldn’t expect a breakthrough in battery life.
For owners of the iPhone 15 Pro and older, the upgrade may be more noticeable — but the final assessment should wait until the September presentation and the first independent tests. For now, this is a leak, and these figures should be treated as a guideline, not as final specifications.
