iPhone 17 Air will be released with a battery case, but there is a better alternative.

Charles Martin from AppleInsider:

Apple will be bringing back a battery-case accessory for its planned iPhone 17 Air to help give the super-slim model all-day battery life.

While the novelty of a super-thin, super-light iPhone is intended to encourage upgrades from older models, the slim design necessitates a smaller battery, and so reduced battery time.

Apple intends to offset this disadvantage by offering an iPhone 17 Air (or iPhone 17 Slim) case that adds its own battery pack, according to a new report from The Information. Adding a thicker battery case would of course undo some of the benefit of a slimmer iPhone, but it's an option that will restore longer battery life.

Battery cases are not new — Apple itself released one for the iPhone 6 and 6s back in 2015. Apple ceased selling a battery case once it released the MagSafe Battery Pack in 2021.

A criticism of both the battery case and its MagSafe successor was that it added bulk to the iPhone. The reported new battery case for the slim model would inevitably do the same, but reportedly Apple believes it's necessary.

That's because Apple's own internal testing of the new model suggests that only between 60% and 70% of users will still get a full day's use of the slimmer, lighter iPhone Air.

That does mean a majority of iPhone 17 Air users will not need to recharge during the day. However, with current iPhone models, it's claimed that this compares poorly to the 80% to even 90% of users who get a full day from a single charge.

People who buy the iPhone 17 Air will be fully aware of its limitations because you can clearly see those limitations, so a battery case would defeat the purpose of the slim device. What makes more sense is a stronger set of magnets and a more robust MagSafe Battery Pack that could be used by all iPhone 17 devices.