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iPhone 16 Pro Max 80% Charge Limit: One Year Later, Was It Worth It?
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This doesn't surprise me. I've owned an EV for a few years and have read a lot of research papers on battery degradation in the interest of extending the life of my car. From the research I've seen, you'll only get a marginal benefit from limiting the charge to 80%. Lithium batteries have what's known as a central graphite peak that occurs somewhere between 57-73%, depending on battery chemistry, and charging above that level results in much faster degradation. So if you wanted to significantly reduce degradation, you would likely need to limit charging to 55% to be safe, but that just isn't going to be practical for a phone, so might as well just charge to 100% and get a battery replacement after a few years if you plan to keep the phone for a long time.
Research paper showing battery degradation at different levels of charge... see Figure 5: https://iopscience.iop.org/article/10.1149/2.0411609jes/pdf
Research paper showing battery degradation at different levels of charge... see Figure 5: https://iopscience.iop.org/article/10.1149/2.0411609jes/pdf
It depends entirely on your usage. I rarely get below 30% as it is, so the trade of that extra 20% for a continually high-performing battery two years later is absolutely worth it. I've lost nothing at all and still have a great piece of hardware I can surely continue to use for another couple of years.
Obviously, if you routinely plow through battery every day like a buddy of mine does, it's not a good tradeoff!
I have the same amount of time, less cycles and a 95 charge limit and I'm at 86
I charge my EV to 75%, as a retired guy that suits my needs, the charge lasts about a month. I charge my 15PM to 80% ev nite. I don’t find that I am limiting my life by not charging to 100%. Actually, I would be limiting my life if I charged it to 100% because I’d have to alter my lifestyle to fit the charge into my day. My battery first use was Nov ‘23, it’s at 96% on 242 cycles. I plan to keep this phone until it doesn’t make it 24 hr w/o a charge.
I do find my lifestyle limited by charging my watch to 80%. I monitor the time it takes to charge and try to pull it off the charger around 80%. This is a PITA even though I do it while showering and having dinner. Why didn’t Apple add the 80% option to it’s watches? I just traded my S-8 wifi watch for a U3. I had it since Nov ‘22 and it was at 83%. For the past 3 mo I have needed to take it to 100% but it still needed a boost to make 24 hrs. I wore it when sleeping. I’ve had the U3 a week and I find I’m charging when ~35% and it takes ~30 min to get to 80%. If I were to let it go down to ~20% then charging would interrupt my day’s routine. Because I sleep with the watch I think concern about lifestyle is overblown. I have to find a good time to charge it and stick to it.
I do find my lifestyle limited by charging my watch to 80%. I monitor the time it takes to charge and try to pull it off the charger around 80%. This is a PITA even though I do it while showering and having dinner. Why didn’t Apple add the 80% option to it’s watches? I just traded my S-8 wifi watch for a U3. I had it since Nov ‘22 and it was at 83%. For the past 3 mo I have needed to take it to 100% but it still needed a boost to make 24 hrs. I wore it when sleeping. I’ve had the U3 a week and I find I’m charging when ~35% and it takes ~30 min to get to 80%. If I were to let it go down to ~20% then charging would interrupt my day’s routine. Because I sleep with the watch I think concern about lifestyle is overblown. I have to find a good time to charge it and stick to it.
Come back with this article after 3 years and report because thats when all the good information happens on batteries and them going down with lower capacities. One year reports apparently don't mean much.
I have often wondered which is better 80% limit and charge every day or 100% charging but charging every other day most of the time, thus reducing cycles. Thoughts?
With the iPhone 15 series, I did an experiment and kept my iPhone's Charge Limit set at 80 percent for an entire year. It provided an interesting look at the impact of charge limits on battery longevity, so I decided to repeat it for the iPhone 16 line.
Since September 2024, my iPhone 16 Pro Max has been limited to an 80 percent charge, with no cheating. As of today, my battery's maximum capacity is at 94 percent with 299 charge cycles.
With last year's test, I spent a lot of time with my battery below 20 percent. I saw some comments suggesting that draining it so low could also affect battery capacity over time, so this year, I tried hard to keep my battery between 20 and 80 percent. I wasn't always successful, but my iPhone 16 Pro Max was in that middle charge area most of the time.
You can compare your own battery health with mine, but my guess is that my 94 percent battery capacity is about average, regardless of whether charging limits are on or off. In fact, my iPhone 15 Pro Max was also at 94 percent capacity at the 12 month mark when I did this same test last year.
I did a mix of charging via MagSafe and charging with USB-C, and my iPhone 16 Pro Max can get hot when charging over MagSafe, especially with MagSafe battery packs. Since I was trying to keep above a 20 percent charge, I did more wireless charging when I was out. I can't help but wonder if heat was an issue this year.
It continued to be inconvenient limiting my iPhone battery to an 80 percent charge. It was fine when home, but if I was out and wanted to use the camera or needed GPS, it often wasn't enough battery. When you set an 80 percent charge limit, the iPhone will charge to full every so often to calibrate, and I appreciated surprise days with 20 percent extra battery.
If I had to guess, I probably had a 50/50 split between MagSafe charging and fast charging with USB-C. Most charging was indoors at around 72 degrees, but there were times when I was outdoors with a battery pack in warmer conditions.
I use my older iPhones for software tests, so my iPhone 15 Pro Max is still around. At the two year mark, its capacity is 88 percent, down from 94 percent in September 2024. It has 352 cycles, and I've kept it at the 80 percent limit.
During this year's testing, my iPhone 16 Pro Max battery was still at around 98 percent just a couple of months ago, so I thought the limit was having more of an impact, but I saw a decent drop as we got closer to September. It was even at 95 percent about a week ago, but now I'm down to 94 percent.
I now have two years of data with my iPhone limited to an 80 percent charge, and I don't think it's been worth it. My coworker who also has a 16 Pro Max did not have an 80 percent charge limit set, and his battery capacity is 96 percent with 308 charge cycles.
Maybe setting an 80 percent limit improves battery health over a longer period of time, but over a one-year period, the results have been disappointing. Setting charging to a 90 or 95 percent might make more sense.
I have upgraded to the iPhone 17 Pro Max and did already limit it to an 80 percent charge for another 12-month test. I'm interested to see how the larger battery changes things, and whether the switch to aluminum will make a difference.
What's your iPhone battery capacity and cycle count? Let me know in the comments below, and weigh in on whether you think the 80 percent charge limit is a good idea.
Article Link: iPhone 16 Pro Max 80% Charge Limit: One Year Later, Was It Worth It?
Sold my iPhone 15pro after using it for 2 years with max charge set to 80%.
It had 90% of maximum capacity and 549 cycles.
So, yes it does definitely have a positive impact. The “optimize battery charging” mode on my old iPhone 13 Pro had before selling it 83% of maximum capacity.
It had 90% of maximum capacity and 549 cycles.
So, yes it does definitely have a positive impact. The “optimize battery charging” mode on my old iPhone 13 Pro had before selling it 83% of maximum capacity.
Tried the same on multiple phones. The only thing that makes a difference is wireless charging or not. Phones using wireless charging suffers significantly worste battery after two years. probably the heat and uneven charging that takes it toll.
This. I got a new battery for my 13 PM a couple weeks ago as I didn't care for any of the new offerings. It was at 81% after almost 4 years. It only cost $90. Why would I worry about stopping at 80% and not letting it go below 20%? I'm going to stress for years about being in a 60% window when I can get a new battery for $90? Makes no sense how people baby their batteries so much.
I still don't get it. Why limit the capacity of your iPhone to 80% during the first years, just to avoid having an iPhone with less than 80% capacity in 3-4 years? Doing this basically gives you the future situation you're trying to avoid right now and for certain.
I agree, I get my dad’s phone changed once a year too. Can’t beat a fresh phone.
There is some logic to it, but mostly for devices plugged in 24/7 like Mac or iPad but as far as I know it’s not a first party feature on both those devices. Eg, on my home bridge laptop I’ve removed the battery and it runs direct from AC. I recall reading about someone who put an iPhone 15 as a car head unit with the battery removed, according to that post iPhone’s before the 15 could not be run without a battery. Funny how both charge % limitation and this, both came with the 15 series.
iPhone 16 Pro Max
First use October 2024. 226 cycles, 100% health.
My phone was never discharged to 0%. Charged always to 80%. About 5 times charged to 100% when planning longer trekking. Always carry Magsafe Philips battery pack and using older iPhone for some tasks like workout recording or navigation.
First use October 2024. 226 cycles, 100% health.
My phone was never discharged to 0%. Charged always to 80%. About 5 times charged to 100% when planning longer trekking. Always carry Magsafe Philips battery pack and using older iPhone for some tasks like workout recording or navigation.
That’s good to hear since my 15 Pro has had 304 cycles since 9/23 and has 89% health. Maybe I will plateau for a while.
I always use USB-C only, almost exclusively over night.
Mine has gotten below 15% but perhaps a couple of times at most, when charging didn’t complete, etc.
I do have Optimized Battery Charging enabled all the time.
I charged my 15Pro to 80% over usb-C and after 468 cycles I am down to 90%.
My theory is that this is the result of using a high power charger (>30W). Would it be better to use a 5W or 10W charger?
For electric cars, there are strong recommendations not to always use DC fast chargers because the battery health really suffers from that.
What does this group think?
I think you are seeing normal aging with your battery. The phone is 2 years old and still has 90% capacity.