From 2023, Apple’s new iPhones have an 80% charge limit for those who want to extend battery life. Charging to 80% rather than 100% is supposed to put less stress on the battery, improving its longevity.
For the past three years I have used this setting on my iPhone. I started with the iPhone 15 Pro Max, then the iPhone 16 Pro Max, and most recently the iPhone 17 Pro Max.
After 12 months with a maximum charge of 80%, my iPhone 17 Pro Max has a maximum capacity of 97%. with a cycle count of 277.
Last year, my iPhone 16 Pro Max had 94% capacity after 12 months and in 2024, my iPhone 15 Pro Max also had 94% capacity.
During the year that I tested the iPhone 16 Pro Max, I tried not to let the battery dip below 20%. This year I did the same thing, but I also tried to charge more via USB-C than Qi2 or MagSafe. I’m not sure if this helped, but the 97% capacity is the best I’ve ever gotten with the charge limit turned on.
I don’t know how my battery performance compares to others, but if you’ve kept yours at 100%, you can compare your capacity to mine to see if there’s any real difference.
Apple switched to aluminum and added vapor chamber cooling with the iPhone 17 Pro Max, and I thought my iPhone spent less time at uncomfortable temperatures than the iPhone 16 Pro Max. It may be that the vapor chamber cooling made the biggest difference and that the wireless charging limitation didn’t matter.
I no longer use the iPhone 15 Pro Max or the iPhone 16 Pro Max as my primary iPhones, but I use them daily as test devices. They still have the 80% limit turned on, so I can share some long-term battery results.
- iPhone 15 Pro Max (36 months) – 88%, 369 cycles
- iPhone 16 Pro Max (24 months) – 93%, 343 cycles
- iPhone 17 Pro Max (12 months) – 97%, 277 cycles
Last year, my iPhone 16 Pro Max reached 299 cycles by September 24th. This year I’m only at 277 cycles. It’s been almost two weeks longer than I usually report results too, so the larger battery meant less charging.
The iPhone 17 Pro Max has a larger battery and faster charging than the iPhone 16 Pro Max, so an 80% charge limit wasn’t as difficult to live with as it used to be. I rarely ran out of battery, although I still took a battery with me to most places. My favorite battery packs right now are the ones with built-in USB-C cables, especially the ones that can attach magnetically to my iPhone but charge it via USB-C. It’s faster charging that’s still convenient. I also continue to be a fan of super-thin battery packs that add little bulk and weight to an iPhone.
For the iPhone 15 Pro Max and iPhone 16 Pro Max, I didn’t think sacrificing a fifth of my battery was worth the capacity I got, and that’s mostly still the case. I guess my 97% capacity isn’t too far off from the battery status readings on iPhones that didn’t have the charge cap turned on.
As for older devices, my two-year-old iPhone 16 Pro Max lost just 1% capacity from 2025 to 2026, and my iPhone 15 Pro Max didn’t lose any capacity during the year. Both phones had fewer battery cycles (44 and 17, respectively), but they maintain capacity even after being turned off for short periods of time throughout the year.
The most practical way to manage battery health is to use Optimized Battery Charging, as it minimizes the time spent with the battery at 100% while still fully charging it. Setting a limit of 80% and then turning it off on the days you need it is also a good compromise that could save you battery capacity over time. Apple also has 90 and 95% options, which may be a better choice.
My iPhone 18 Pro Max is already set to 80%, so I’ll check back in September 2027. I’ll continue to charge via USB-C when I can, and I’m curious how the even larger battery will impact longevity and what the 80% limit looks like on a day-to-day basis.
What is your iPhone battery capacity and number of cycles? Share it in the comments below and consider whether you think it’s worth limiting your battery charge.
