Iphone 18 Pro Max Introduces New Feature for Massive Battery Drain
WHO:
9to5Mac - Apple is the company introducing the iPhone 18 Pro Max.
WHAT:
9to5Mac - The iPhone 18 Pro Max has a battery capacity rated at 5,567mAh (21.75Wh) for the eSIM-only model shipped in the US, and 5,391mAh (21.06Wh) for the European model with a physical SIM card slot.
GSMArena.com - The US transport regulator allowed Apple's shipping method back in June 2025, which circumvents the shipping restrictions for batteries over 20Wh.
GSMArena.com - The UN Sub-Committee of Experts on the Transport of Dangerous Goods is considering a proposal to update the 20Wh boundary for single-cell batteries, with potential changes expected in 2029.
9to5Mac - The iPhone 18 Pro Max uses an "innovative battery-firmware solution" that limits battery capacity to below 20 Wh from the time it’s manufactured through its transport from the factory until activated by the user.
MacRumors - The Prepare to Ship process may take only a few minutes, but if starting with a full charge, it can take up to a couple of hours to complete.
MacRumors - If the iPhone is erased, it cannot be used while the battery discharges during the Prepare to Ship process.
9to5Mac - The iPhone 18 Pro Max has a battery capacity over 20 watt-hours (Wh).
MacRumors - The iPhone 18 Pro Max requires a new "Prepare to Ship" feature to limit battery capacity during shipping.
MacRumors - The "Prepare to Ship" feature discharges the battery to below 20 Wh and sets a charge limit.
MacRumors - The iPhone can become "warmer than usual" during the Prepare to Ship process.
MacRumors - After the Prepare to Ship process, the iPhone displays a "Ready to Ship" status in Settings.
WHERE:
9to5Mac - The shipping requirements apply to most countries and regions for products with a single-cell battery over 20 Wh.
WHEN:
MacRumors - There could be a 14-day waiting period before the Prepare to Ship feature can be undone.
WHY:
9to5Mac - The additional shipping requirements are due to the iPhone 18 Pro Max's battery capacity exceeding 20 Wh.
MacRumors - The limit is added to meet shipping requirements and ensure safety for shipping and air travel.
HOW:
9to5Mac - Users can access the Prepare to Ship option by navigating to Settings > General > Transfer or Reset iPhone > Prepare to Ship.
9to5Mac - The iPhone 18 Pro Max uses an "innovative battery-firmware solution" to limit battery capacity until activated by the user.
MacRumors - Users can access the Prepare to Ship option by navigating to Settings > General > Transfer or Reset iPhone > Prepare to Ship.
(UPDATED September 19, 2026 18:55 UTC)
The iPhone 18 Pro Max features a battery capacity of 5,567mAh for the eSIM-only model in the US, while the European version with a physical SIM card slot has a slightly smaller capacity of 5,391mAh. This shipping method was approved by the US transport regulator in June 2025, allowing Apple to bypass certain restrictions on batteries over 20Wh. Meanwhile, the UN Sub-Committee of Experts on the Transport of Dangerous Goods is reviewing a proposal to potentially update the 20Wh limit for single-cell batteries, with any changes anticipated in 2029.
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(UPDATED September 19, 2026 16:57 UTC)
The new iPhone 18 Pro Max features an innovative battery-firmware solution that limits its battery capacity to below 20 watt-hours from the moment it leaves the factory until it's activated by the user. While the Prepare to Ship process can take just a few minutes, if the device starts with a full charge, it may take a couple of hours to complete, and users should note that if the iPhone is erased, it won't be usable while the battery discharges during this process. To access the Prepare to Ship option, users can navigate to Settings, then General, followed by Transfer or Reset iPhone, and finally select Prepare to Ship.
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(UPDATED September 19, 2026 16:00 UTC)
Apple is set to introduce the iPhone 18 Pro Max, which boasts a battery capacity exceeding 20 watt-hours. To comply with shipping safety requirements, the device will utilize a new "Prepare to Ship" feature that discharges the battery below 20 watt-hours and sets a charge limit, potentially causing the phone to become warmer than usual during this process. Users will need to navigate to Settings to access this feature, and there may be a 14-day waiting period before they can undo it after shipping.