“Prepare to Ship” Battery Drain and Limit
The iPhone 18 Pro Max has a battery capacity over 20 watt-hours, which means there are additional shipping requirements. If an iPhone 18 Pro Max needs to be shipped somewhere, its maximum battery capacity has to be limited through firmware.
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Customers who need to ship the iPhone 18 Pro Max for repair, trade-in, or other purposes have to use a new Prepare to Ship feature. Prepare to Ship discharges the battery to below 20Wh and sets a charge limit so the iPhone stays below the threshold during the shipping process.
Laptops, of course, have larger batteries, but they aren’t affected because each cell is below the limit.
