You should regularly take a moment to check on your iPhone’s battery life. And given how easy Apple made it starting in iOS 11.3, we really have no excuse. All you have to do is hit Settings > Battery > Battery Health, and you’ll be able to see the maximum capacity of your iPhone’s battery, ensure “Optimised Battery Charging” is enabled to give you as much battery life as possible, and check for that handy little “you’re screwed” message from Apple if your battery has degraded enough that it’s starting to affect your iPhone’s performance.
Once you install iOS 14.5, however, you might see a new prompt:
Your battery health reporting system is recalibrating Maximum Capacity and Peak Performance Capability. This process may take a few weeks. Learn more…
If you don’t see this message, don’t worry. It’s only going to show up if you own an iPhone 11, iPhone 11 Pro, and iPhone 11 Pro Max, as it’s Apple’s solution for correcting inaccurate battery estimates for these iPhones from previous versions of iOS.
Here’s how the calibration process will go down: Your device will show that message for up to a few weeks, and during this time, it’s possible that you won’t see any warnings about a degraded battery while iOS chugs along. You’re not in the clear per se; your device might simply be unable to make a recommendation without a more accurate assessment of your battery’s maximum capacity (and how that affects your iPhone’s performance).
Once the process is done, you’ll either get an updated Maximum Capacity and any warnings that might come from it, or you’ll see a slightly more troublesome message:
Recalibration of the battery health reporting system was not successful. An Apple Authorised Service Provider can replace the battery free of charge to restore full performance and capacity. More about service options…
As Apple describes, this doesn’t mean your iPhone is going to explode or anything; rather, you might be able to score a free battery replacement if your iPhone is still covered by its regular warranty, AppleCare+, or the more nebulous “consumer law.” Consider contacting Apple Support to see what your options are, if any.
Additionally, notes Apple:
You can also contact Apple Support if you previously paid to service an out-of-warranty battery for your iPhone 11, iPhone 11 Pro, or iPhone 11 Pro Max after seeing a battery health degraded message or experiencing unexpected battery behaviour.
While it’s never great to have an iPhone with a degraded battery, perhaps you’ll luck out and get a lovely new replacement (or some kind of reimbursement for a replacement you already paid for).