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iPhone 16 Pro Max 80% Charge Limit: One Year Later, Was It Worth It?
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This discussion is quite interesting. Some people start by trusting the scientific reasoning and then try to prove they can achieve the same results themselves, while others rely only on their own experience and show that it works in practice. Personally, I lean toward the view of “knowing the theory exists, but since I haven’t tested it myself,” I decided to use this chance to verify it. The principles I know are:
1. Lithium batteries don’t handle high temperatures well.
2. Prolonged high voltage or very low voltage can damage lithium batteries.
So my strategy has been to test based on this knowledge: I set the charge limit to 85%, I rarely use fast charging (even though I’ve heard Apple manages the charging current to control heat), and I avoid letting the battery drop below 25%.
So far, the results are: 125 cycles, 9 months of use, and still 100% battery health (iPhone 16 Pro). I’ll keep going and see what it looks like after a full year…
1. Lithium batteries don’t handle high temperatures well.
2. Prolonged high voltage or very low voltage can damage lithium batteries.
So my strategy has been to test based on this knowledge: I set the charge limit to 85%, I rarely use fast charging (even though I’ve heard Apple manages the charging current to control heat), and I avoid letting the battery drop below 25%.
So far, the results are: 125 cycles, 9 months of use, and still 100% battery health (iPhone 16 Pro). I’ll keep going and see what it looks like after a full year…
My 15 pro, that's been at "adaptive powermode" that always charges to 100% the entire 2 years since I got it, and that almost exclusively have been charged wirelessly, is at 362 cycles, and the capacity is also 88%.
So, anecdotally, adaptive and charging to 100% is just as good as capping it at 80% but with none of the downsides of running out of "juice" 20% earlier...
Pro Max models are generally tough when it comes to battery performance. Many people have 90-95% in two years.
I am much more interested in someone doing such test with “iPhone for smaller hands” like Pro. Because my gf’s 16 Pro is already 90%, purchased at launch. And I can see it is a common problem in many new regular Pro models
I am much more interested in someone doing such test with “iPhone for smaller hands” like Pro. Because my gf’s 16 Pro is already 90%, purchased at launch. And I can see it is a common problem in many new regular Pro models
90% might not really mean the capacity is 90%. From some other andorid phone tests, I read when their battery reports 90% health, the actual capacity can be 85% and for such reduced capacity, the charging time raises to 150%. This also roughly matches my experience with iphone.
I have iPhone 16. Maximum capacity 100% with 199 cycle count. For me it seems to work cos usually after year without charge limit it usually around 95% or less.
I also only charge it with Apple USB C charger. Never used MagSafe.
My iPad Pro M4 seem same thing too. 100% with 78 cycle count.
EDIT: Noticed I actually set charge limit to 90% instead of 80%. Both iPhone and iPad.
I also only charge it with Apple USB C charger. Never used MagSafe.
My iPad Pro M4 seem same thing too. 100% with 78 cycle count.
EDIT: Noticed I actually set charge limit to 90% instead of 80%. Both iPhone and iPad.
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I tortured my iPhone 15 Pro Max battery, thinking that if it'd get below 80% health within two years then I'd get a free batter replacement. And it degrading to 80% would still be better than to only use 80% of the battery from day one.
Didn't quite keep it for the full two years, and it only got down to 87%.
It's simply not worth it to artificially limit your phone as if it was shipped with a smaller battery. At this point that whole thing is basically superstition going back to older technology, where it might have been more relevant. The same as with how you are, or are not, supposed to fully discharge the battery before charging it again.
Just live your life.
Didn't quite keep it for the full two years, and it only got down to 87%.
It's simply not worth it to artificially limit your phone as if it was shipped with a smaller battery. At this point that whole thing is basically superstition going back to older technology, where it might have been more relevant. The same as with how you are, or are not, supposed to fully discharge the battery before charging it again.
Just live your life.
I think this applies more to things like iPads that may be plugged in most of the time. For example, my mother leaves her iPad plugged in 24x7. Her older iPad air had no charging limits and is now down to 69% battery health after 3 years. Limiting her newer 2 year old iPad to 80% has 91% health. Not a perfect test, but I think similar to EVs and other things its a question of not charging to 100% but *keeping* at 100%.
I also assume Apple may provide some sort of buffer where 100% isn't truly 100%, but thats a guess (again speculating based on EV battery stuff)
I also assume Apple may provide some sort of buffer where 100% isn't truly 100%, but thats a guess (again speculating based on EV battery stuff)
15 Pro Max, after 2 years, 337 cycles and 95%. I charge to 80 usually and once a week to 100, as I heard that might do the trick longterm 
. I think if you have very irregular charging schedules and want to use your phones for more than 2 years it could be worth it. I am al lot in my car with a magsafe charger and to keep it at 100% all the time might add to decrease battery health faster than to keep it at 80%. Also the optimized Apple thingi just works if your life is like clockwork every day. But in the end its a battery and live will go on. Nevertheless they give you the option and that's a good thing, as on Macs you have to pay for it with third party apps.
. I think if you have very irregular charging schedules and want to use your phones for more than 2 years it could be worth it. I am al lot in my car with a magsafe charger and to keep it at 100% all the time might add to decrease battery health faster than to keep it at 80%. Also the optimized Apple thingi just works if your life is like clockwork every day. But in the end its a battery and live will go on. Nevertheless they give you the option and that's a good thing, as on Macs you have to pay for it with third party apps.I agree, I have personally wasted much time worrying about the battery on older iPhones.
However, there are 2 things to keep in mind.
All iPhones since the 16 have batteries installed that can not easily be removed by the user.
The new bonding technology benefits nobody but Apple, because it’s even more intimidating that the pull tabs. I’ve replaced many batteries in iPhones but will not tinker with electronics in the newest models.
So, it is not an option anymore to replace the battery yourself like it was before.
Also, many people can either not afford to upgrade more than once every 3-5 years, and those that do might want to hand down their phone and still have it hold a decent charge, like me.
This will be my mums phone at some point, so might as well leave her some battery.
Apart from these scenarios I agree with you of course, it’s bad for the mind to worry about things like battery health. Chemistry can’t be stopped.
Yeah I agree. Switch 2, I use it mostly docked so the 90% limit is probably a good idea. I disable it when I know I’m taking it out to use handheld.
I retired my 13 Pro Max when I got a 17PM. The menu doesn’t have as much data but that still had 94% health after 4 years of full charging. Now admittedly, I don’t believe the 94% stat, but it still had good battery life. I never got around to checking it with Coconut battery.
I'm such a light user I don't bother with charge limits. I go three or four days between charges, so I haven't even checked my battery health since buying my 16PM, to be honest.
Nah this didn’t help. I’m at more than double your cycle count with 93% in one year. It’s about the same.
10 years ago I used a Samsung Galaxy Note phone.
It had a plastic removable back.
The plastic back was functional, it didn't scratch or crack and because I kept the phone in a case, I never saw the back of the phone so it didn't matter what it was made from anyway.
I could buy a new battery for $20, slide the plastic back off of the phone and replace the old battery in seconds!
Which meant we didn't live in a world of 80% paranoia and the reviewer could have spent their time doing something more productive that agonising over their battery health.
How lucky are we that now we can take time to travel to an Apple store and pay $100 for someone else to change the battery for us!
Isn't progress wonderful!
It had a plastic removable back.
The plastic back was functional, it didn't scratch or crack and because I kept the phone in a case, I never saw the back of the phone so it didn't matter what it was made from anyway.
I could buy a new battery for $20, slide the plastic back off of the phone and replace the old battery in seconds!
Which meant we didn't live in a world of 80% paranoia and the reviewer could have spent their time doing something more productive that agonising over their battery health.
How lucky are we that now we can take time to travel to an Apple store and pay $100 for someone else to change the battery for us!
Isn't progress wonderful!