Apple has integrated silicon-carbon anode battery technology into the iPhone 18 Pro Max, pushing its capacity beyond the 20 Wh threshold. The US eSIM model features a capacity of 21.75 Wh (5567 mAh), while the European version with a physical SIM slot offers 21.06 Wh (5391 mAh).
International aviation regulations classify lithium batteries exceeding 20 Wh as Class 9 dangerous goods, imposing strict logistics and certification requirements. To bypass these hardware-based restrictions, Apple implemented a firmware-level solution that limits the battery capacity to under 20 Wh during manufacturing and transit.
The software restriction is automatically lifted upon the device's initial activation by the end user, ensuring full battery capacity is available for daily use. This approach allows Apple to maintain high energy density without altering hardware designs or incurring additional physical production costs.
For post-purchase logistics, such as returns or repairs, Apple introduced a Prepare to Ship feature in iOS. This function discharges the battery to below the 20 Wh limit and locks the charging capacity, allowing the device to meet aviation safety standards for shipping.
