Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

MacRumors

macrumors bot
Original poster
Apr 12, 2001
67,487
37,756


With the iPhone 15 models that came out last year, Apple added an opt-in battery setting that limits maximum charge to 80 percent. The idea is that never charging the iPhone above 80 percent will increase battery longevity, so I kept my iPhone at that 80 percent limit from September 2023 to now, with no cheating.

iPhone-15-Pro-lineup.jpg

My iPhone 15 Pro Max battery level is currently at 94 percent with 299 cycles. For a lot of 2024, my battery level stayed above 97 percent, but it started dropping more rapidly over the last couple of months.

I left my iPhone at that 80 percent limit and at no point turned the setting off or tweaked it. There were some days when I ran out of battery because I was without a charger for most of the day, and there were other times that I had to bring a battery along to make sure I didn't run out of power. It wasn't always convenient to keep it at 80 percent, but there were days when it didn't have too much of an impact.

iphone-15-pro-max-battery-test.jpg

It was always a treat when the iPhone randomly decided to charge to 100 percent, which is something Apple has baked in to the 80 percent limit to ensure the battery level stays calibrated.

For the most part, I charged using USB-C rather than MagSafe, but there was some MagSafe charging mixed in. There was probably a 70/30 split between wired charging and MagSafe charging. I did often let my battery get quite low before charging, and it didn't sit on the charger for long periods of time too often. Most charging was done in a room at 72 degrees. I'm adding this context because temperature is a factor that can affect battery longevity, and wireless charging is warmer than wired charging.

You can compare your level battery to mine, but here are a couple other metrics from MacRumors staff that also have an iPhone 15 Pro Max and did not have the battery level limited.
  • Current capacity: 87%. Cycles: 329
  • Current capacity: 90%. Cycles: 271
I don't have a lot of data points for comparison, but it does seem that limiting the charge to 80 percent kept my maximum battery capacity higher than what my co-workers are seeing, but there isn't a major difference. I have four percent more battery at 28 more cycles, and I'm not sure suffering through an 80 percent battery limit for 12 months was ultimately worth it.

It's possible that the real gains from an 80 percent limit will come in two or three years rather than a single year, and I'll keep it limited to 80 percent to see the longer term impact.

I did set my iPhone 16 Pro Max to an 80 percent limit, but I don't know if I want to continue the test given the lackluster results I had from 2023 to 2024. Will the thermal changes in the iPhone 16 models make any difference? Maybe, maybe not. There's a 90 percent charge limit option too, and that might be more feasible than 80 percent for most people, especially those that have phones with smaller batteries.

Let me know your current battery capacity and cycle count in the comments below, and weigh in on whether you think Apple's limits are worthwhile.

Article Link: Apple's 80% Charging Limit for iPhone: How Much Did It Help After a Year?
 
Honestly I don't see the point of it. Yeah it might give your battery a little more longevity, but if its going dead on you throughout the day because you only charged it to 80% it seems like a complete waste to me.
 
15 Pro Max
Using 80% limit since day 1
93% capacity
286 cycles

I was a bit disappointed as I thought 80% limit would keep capacity better. I remember my XS Max was at 100%, my X was at 96%, and a couple since then were 97-98%, this is the lowest I’ve had in one year and I’m actually skipping upgrading this year. Weird. I rarely use MagSafe. I have it, but 10% charging at most was MagSafe. And I have a fan to keep it cool while on MagSafe.

Also, previous phones I nursed the batteries manually, not going past 80%.

Kinda disappointing results for using the 80% limit.
 
I find there is a high correlation between people who get a new phone every year or two, and people who obsess over their battery health. The amount of obsession over battery health I hear on the Accidental Tech Podcast is baffling, and those jokers get new phones every year or two.
 
iPhone 11 Pro, bought at launch. Never babied it around but charged mostly with 5v charger that came with my first iPhone, sometimes rarely 10v and 12v chargers: 86%. I always let it discharge to minimum of 3-7% and only then start charging and always charge to full
 
  • Wow
Reactions: NetMage
I have about 214 charging cycles Since November 2023 with pro max. Always charged to 80%. Up until around end of July I kept 100% capacity. With the 17.6.1 my capacity shrunk down to 96% in a couple of days. Pretty annoying. Luckily 18 solved it
 
  • Haha
Reactions: ignatius345
The idea of charging between 20 and 80% was born because of a coincidence (read more here) and it is not based on anything truly scientific. The best thing a user can do is to let macOS/iOS/iPadOS manage the battery as it wants.
Actually, always keep your device as charged as you need, that is, use it normally. When it falls below 45-50%, charge it up to 100%! The only thing you should try to avoid—though nothing dramatic is going to happen if you forget this a few times—is to keep it plugged at 100% for too much time.
My 2023 MBP has 226 cycles and 98% health (though Coconut Battery says about 95%). I've charged it to 100% always and charged anytime between 10 and 50% when needed. I believe we users have many more important things to worry about than battery health.
 
My partner & I both got a launch day 15 Pro Max. Both of us use “optimized charging” not the 80% limit. We use only wired chargers, no MagSafe. We live in mostly 70° year round weather, rarely goes over 90 or under 50. I charge overnight, he does not. I play a decent amount of games on my phone, Pokémon go, genshin, Diablo, he pretty much watches YouTube and shops.

I have 288 cycles, 91% battery health.

He has 257 cycles, still 100% battery health.

I have no idea how he still has 100%. Either it’s down to the lottery and his came with a much higher starting capacity than mine, his is having a bug with reporting the actual health, or our habits of overnight charging and hot phone games really make all the difference.
 
Optimized charging except in trips with intense photo usage where I limit to 80% during the day (keeping it plug to external battery once I consume 20%), and at nights changed it back to optimized again.

170 cycles, 96%, always with usb c. Never consumed more than 50% of battery in one day.
 
  • Like
Reactions: Brian_v11
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.