On iPhone 15 models, iOS 18 will recommend that users set a particular charging limit for their device based on their recent usage habits, with the aim of potentially improving their iPhone battery's lifespan by reducing the time that the battery is fully charged.
All four iPhone 15 models feature a setting that prevents the devices from charging beyond 80% while toggled on, and iOS 18 expands the feature by adding new 85%, 90%, and 95% charging limit options. With the new limit options, iOS 18 now takes a proactive approach to improving battery longevity by recommending a specific charging limit to users via a notification.
The recommendation also appears in the Settings app under Battery → Charging. The charging limit feature remains exclusive to the iPhone 15 lineup on the first iOS 18 beta, with the option not found on the iPhone 14 Pro or older.
In a related change, anecdotal reports suggest that iOS 18 could be recalibrating some devices' maximum battery capacity percentage. In Settings ➝ Battery ➝ Battery Health, "Maximum Capacity" is a measure of battery capacity relative to when the device was new. Lower capacity can result in fewer hours of usage between charges.
The first iOS 18 beta is available for Apple Developer Program members, and a public beta will follow in July. After beta testing is complete, the update should be widely released to all users with an iPhone XS or newer in September.
Monday September 15, 2025 12:00 am PDT by Eric Slivka
Update 10:06 a.m.: iOS 26 is rolling out now, though it may take a bit for all users to see it, so keep checking!
Today's the day! Apple is about to release iOS 26, which will deliver the biggest redesign since iOS 7 and bring a range of new features and improvements to iPhones worldwide. It's Apple's biggest software update of the year, and Apple announced at last week's iPhone event that...
Sunday September 14, 2025 8:45 am PDT by Joe Rossignol
Apple's annual September event is now in the rearview mirror, with the iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, iPhone Air, Apple Watch Series 11, Apple Watch Ultra 3, Apple Watch SE 3, and AirPods Pro 3 set to launch this Friday, September 19.
As always, there is more to come. In his Power On newsletter today, Bloomberg's Mark Gurman said Apple plans to release many products in the...
Monday September 15, 2025 10:56 am PDT by Juli Clover
In the iOS 26 release notes, Apple is warning iPhone users that installing the new software might have a temporary impact on battery life, which is normal.
A new support document explains that major iOS updates require background setup like indexing data and files for search, downloading new assets, and updating apps.
Further, Apple says that new features could require more resources,...
Friday September 12, 2025 7:58 am PDT by Tim Hardwick
Apple will launch its new iPhone 17 lineup and ultra-thin iPhone Air in stores on Friday, September 19, and the company has already shown off the new devices at its fall event, which ran with the the tagline "Awe dropping."
The iPhone 17 series brings a host of new features and enhancements. Here's a rundown of the biggest upgrades and changes:
iPhone 17
Display Changes
The iPhone...
Monday September 15, 2025 10:50 am PDT by Juli Clover
Apple today released updated firmware for the AirPods Pro 2 and the AirPods 4, introducing support for the new AirPods features that are included in iOS 26, iPadOS 26, and macOS Tahoe.
The firmware has a build number of 8A356, and it replaces the current 7E93 firmware.
With Apple's new software updates, the AirPods Pro 2 and the AirPods 4 support better audio quality for phone calls and...
Saturday September 13, 2025 10:01 am PDT by Joe Rossignol
The latest iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air models are equipped with Apple's all-new N1 chip for Wi-Fi 7, Bluetooth 6, and Thread connectivity. However, the chip has a Wi-Fi 7 bandwidth limitation.
According to FCC documents reviewed by MacRumors, the N1 chip in all of the new iPhone models supports up to 160 MHz channel bandwidth for Wi-Fi 7, short of the...
Sunday September 14, 2025 1:36 pm PDT by Joe Rossignol
T-Mobile President Jon Freier today shared real-world photos of Apple's boxes for the iPhone Air, iPhone 17 Pro, and iPhone 17 models, which launch on Friday.
Image Credit: Jon Freier
Apple has typically included iPhone box renders in its product environmental reports, but it did not do so for the latest models. However, Apple's iPhone Upgrade Program page does offer some images of the boxes, ...
They’re getting to a point where people can hold onto their iPhones for 10 years. If I’m a shareholder, I’m asking what Tim is doing to replace the lost revenue from iPhone users who aren’t upgrading?
I charge my phone overnight, to 100%, every day ... don't care about battery health/lifespan. Its a consumable, when it doesn't meet my needs anymore it gets replaced
You're reducing the accumulation/creation of dendrites.
Dendrites are crystal-like formations in the cell that grow through the electrolyte, little by little, with each charge and discharge cycle. They cause short-circuit in a cell when they grow all the way through. This is the main way a li-ion cell dies.
Dendrites are formed primarily during deep charging and deep discharging. E.g., when you discharge the battery down to 0%, and when you charge the battery up to 100%. If you stay within the 20%-80% charge range all the time, a modern lithium ion cell can last probably 10x as many cycles compared to a battery that is cycled between 0% and 100%. But staying in that narrow range sacrifices 40% of the battery capacity, so it's pretty undesirable. Indeed, everything about battery design is balancing competing interests and picking 2 of 3 options.
Most battery controllers don't let you go to 0% anyway. When your phone is reporting 0%, it likely really means the battery has 1-3% left but for self-preservation it's not going to let the device turn on in that state. And most folks don't discharge their phone all the way daily anyway - it's a rare occurrence to be plugging in a totally dead phone. But most battery controllers let the battery charge to 100%. So dendrites slowly form.
By limiting the charging to 80%, you're greatly reducing/slowing the formation of dendrites.
But 80% is a bit aggressive in my opinion. Dendrite formation becomes a real problem at the extremes. 90-95% charge limit would be fine I think.
This is looking more and more like something in the hardware of the iPhone 15 models that allows the charging limits as well as this new feature. Maybe something controlling the USB C port or the battery controller itself?
All existing devices since iPhone 6S can do Optimized Battery Charging, which delays charging past 80%. All iPhones can pause charging when high temps are experienced. So we already know existing hardware is capable. This is confirmed by the fact jailbreaking can re-enable this artificially locked feature on iPhone 14 and older. This is a case of pure feature rationing.
