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In-Depth iPhone Battery Experiment Pits Slow Charging Against Fast Charging
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Glad to see that someone took the time to prove what has been said for some time. Just charge it when you need to, however you can.
Exactly. It is almost like they want to have less mobile power.
I always keep my 14 Pro Max plugged in unless I'm out of the house or doing something in the kitchen. Therefore, it rarely dips below 80% battery charge remaining at any time before getting fully charged again. I got this phone the week after the initial iPhone 14 release date over 3 years ago, still have to original battery, and battery health is 90.2%. So this has never been a concern for me.
While technically true, it may not be as definitive as the test suggests.
Battery degradation isn’t linear. So while they appear to have lost more, they could’ve plateaued and the difference could end up being much smaller in the long run.
My own 13P came down from 96% to 87% in just a couple months and had stayed there for over 8 months now. I almost exclusively charge with 20W whenever and don’t follow any charge limits either. It measures 88.6% with Coconut Battery.
Analysis: Does wireless charging wear down your iPhone battery?
We asked readers about their charging habits and the data revealed a surprise.
www.macworld.com
Wireless charging has next to zero impact in battery life.
Yay - that should settle all the debates and MR will now be free of Battery Life Zealots!
Right? 😬
Right? 😬
Sure it does.
“I never charge over 80% so that in 2 years my battery will hold 90% instead of 80% of charge.”
Makes perfect sense. That person is very worried that in 2 years they won’t have access to battery capacity they refuse to use now.
/s
My philosophy is yours. I will enjoy 100% battery today and live with 80% battery in 2 years rather than live with 80% battery from day 1…
It does if staying at 80% (I use 85%) still leaves you with battery at the end of the day because it costs nothing. Why would I sacrifice long term battery health just to plug in for the night at 40% instead of 25%?
The obsession with battery life is starting to get beyond a joke.
IDK... I wake up and pull my phone off its charger. Then I use it throughout the day. And when I go to bed, I return it to its charger. Isn't that how it's supposed to work?
Why does Apple push the 80% charging limit so hard? I literally cannot shut this off on my AW10 or Ultra2. Even with it disabled on both watches, it still only charges to 80 percent most of the time and I have to have it in nightstand mode to charge it to 100% when I want. It occurs to me that maybe Apple might know something more about batteries and battery life than we do. It is IMPOSSIBLE to get anything useful off of the internet because there is so much conflicting information out there.
Did the tests use the same amount of battery? Did they use the phones the same amount of time over the course of the tests only charging the restricted phones more often to achieve that? Did they make sure by the end “cycle counts” matched?
My watches charge to 100% every time. Not sure why you don’t have the same outcome.
What are you trying to say?
All I see are a handful of questions thrown around here.
500 times is a lot for a test, but like quite a few others, I've managed to use one for 6 years x 365 = around 2.190 cycles.
The 'why limit to 80% if you don't use it' argument goes both ways: Why load to 100% if you don't use it anyway? I have never run empty despite limiting to 80% and often scrolling and viewing for hours a day.
The 'why limit to 80% if you don't use it' argument goes both ways: Why load to 100% if you don't use it anyway? I have never run empty despite limiting to 80% and often scrolling and viewing for hours a day.
This is why I always charge to 100% and turn off all the optimised charging BS, it makes sod all difference in the real world. I only charge wirelessly using the fastest possible charge speed on whatever each new iPhone supports at the time, after a year my battery capacity is always around 99% to 100% and the lowest I've ever seen at least on my devices is 98%. The phone is always charged overnight and left at 100% until I wake up.
Same for my Apple watches, and I've used every generation (always the largest size) since it launched, always charge to 100% and after a year the lowest I usually see is 98 to 99%. The lowest I've ever seen was 97%, and again with no optimised battery crap and always charged to 100%. Just use your phone people, charge it and enjoy it, stop micromanaging it.
Same for my Apple watches, and I've used every generation (always the largest size) since it launched, always charge to 100% and after a year the lowest I usually see is 98 to 99%. The lowest I've ever seen was 97%, and again with no optimised battery crap and always charged to 100%. Just use your phone people, charge it and enjoy it, stop micromanaging it.
You're missing two key ideas for why people limit phone charging to 80%:
1. To maintain battery capacity
2. To keep peak performance (voltage)
First, keeping the battery at a lower charge helps maintain its total capacity over time. Battery health affects how much energy it can store. If someone can get through a normal day like on weekdays just fine, then charging only to 80% doesn't really hurt. It actually helps them have better battery life when they really need it, like on weekends or during heavy use.
Second, as batteries degrade, they also lose some voltage output, which affects performance. On phones this might show up as slower processing or throttling. On EV it affects things like motor power.
That said, I personally charge my iPhone to 100% all the time. The extra wear is tiny for me since I upgrade my phone every 2 to 3 years anyway. But with my Tesla I'm much more strict about battery care because even a small amount of degradation feels more noticeable and annoying on a car than on a phone. Hope that makes sense.
I am asking if the tests actually used the same amount of battery overall.
Otherwise it’s like saying I only drive my car 5000 miles a year and have less wear and tear over 3 years than someone who drives theirs 10000 a year.
Apple measures cycles as 0-100% charge equivalents.
After 139 cycles as measured by Apple, my 15Max battery health is 98%, and I got it March 2025 (though it was manufactured in 2024). That’s all I know about my battery. Every 6 months I will lose 2-3% capacity and after 2 years will be at 90%.
Sounds better than limiting myself to 80%-30% and not having a full day charge when I need it.
They only show the graph for the 5-100%, but it doesn't deviate dramatically from linear for the 500 cycles:
More data would be nice, but I'll take the one we have here.
If you regularly need that extra capacity, I agree. But in my case, an 80% charge is more than enough for my typical daily usage on my iPhone 13. And it's not just a few % of capacity you are saving, but preventing a potential expensive battery replacement!
My iPhone 13, approaching 4 years old, still has 89% capacity. I try to limit it to 80% charge using notifications, but I'm not religious about it. But even with a somewhat worn battery, 80% is still more than enough to get me through a typical day on this device.