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Apple's 80% Charging Limit for iPhone: How Much Did It Help After a Year?
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I have a 15 Pro and have had this option enabled since it was offered. First use was September 2023, cycle count is 237 and maximum capacity has just dropped from 100% to 98%. I generally charge once a day, I’m not a very heavy user admittedly but I’m quite happy with how long the battery lasts with this setting enabled so far.
And I'm over here with a 12 mini from 2020 at 75% capacity and wondering if it's time for me to get a new battery installed or if I should wait a while longer...
Glad I saw this article. I had my 16P set at 80% but with Helene coming I am going to change it back to 100% so in case the power goes out i have some juice in the phone.
I don't have time to read all 20 pages of comments but I'll add a few of my own since I used to test and bin li-po battery cells at a previous job...
This is not an exact science. The actual capacity of a cell, the voltage at which it operates, and the correlation between the voltage and capacity, are all slightly variable. This means the percentages (both SOC and health %) are basically educated guesses. Some batteries will degrade faster than others no matter how nicely you treat them, just based on manufacturing or other innate variables. Margin of error is fairly large here, in other words.
Leaving a phone plugged in overnight or all day, whether at 80% or 100%, will degrade a battery faster than letting it sit at a lower voltage. Ideally, a battery around nominal voltage (50%-ish) with small charge windows (40-60%, for instance) will show the least degradation. However this can vary from cell to cell quite a bit too.
Heat is large factor, especially when combined with high SOC. If you do things like play demanding games on your phone while it's plugged in at 100% in a warm environment, OR frequently charge to 100% and let it drain to 0% under the same conditions, those are probably worst case scenarios for your battery.
Charging to 80% overnight (letting it sit like that for hours) and letting it drain to 0% is not necessarily better than than charging to 100% during the day, taking it off the charger as soon as fully charged, and only going down to 20%. Again, this is in theory/on average, and may not be the case for your specific battery/phone.
Never charging to 100% may lead to some calibration drift, or it could stay relatively locked in. Again, this will differ from phone to phone.
Degradation from 100 to 90 capacity will occur faster than degradation from 90 to 80 capacity... typically. This has always been true for my phones. I've had many go down to anywhere from 88-94% over the first year, and then hang out above 85% over the next 2-4 years.
In conclusion: I agree that it's not worth messing with the charge limit setting, for most people. Your battery will degrade no matter what you do, and slowing the curve down by a few months only to end up in the same place eventually anyway isn't worth taking a constant 20% hit. But, do some additional research if you really want to extend that puppy. It can be a fun game to play, if nothing else
This is not an exact science. The actual capacity of a cell, the voltage at which it operates, and the correlation between the voltage and capacity, are all slightly variable. This means the percentages (both SOC and health %) are basically educated guesses. Some batteries will degrade faster than others no matter how nicely you treat them, just based on manufacturing or other innate variables. Margin of error is fairly large here, in other words.
Leaving a phone plugged in overnight or all day, whether at 80% or 100%, will degrade a battery faster than letting it sit at a lower voltage. Ideally, a battery around nominal voltage (50%-ish) with small charge windows (40-60%, for instance) will show the least degradation. However this can vary from cell to cell quite a bit too.
Heat is large factor, especially when combined with high SOC. If you do things like play demanding games on your phone while it's plugged in at 100% in a warm environment, OR frequently charge to 100% and let it drain to 0% under the same conditions, those are probably worst case scenarios for your battery.
Charging to 80% overnight (letting it sit like that for hours) and letting it drain to 0% is not necessarily better than than charging to 100% during the day, taking it off the charger as soon as fully charged, and only going down to 20%. Again, this is in theory/on average, and may not be the case for your specific battery/phone.
Never charging to 100% may lead to some calibration drift, or it could stay relatively locked in. Again, this will differ from phone to phone.
Degradation from 100 to 90 capacity will occur faster than degradation from 90 to 80 capacity... typically. This has always been true for my phones. I've had many go down to anywhere from 88-94% over the first year, and then hang out above 85% over the next 2-4 years.
In conclusion: I agree that it's not worth messing with the charge limit setting, for most people. Your battery will degrade no matter what you do, and slowing the curve down by a few months only to end up in the same place eventually anyway isn't worth taking a constant 20% hit. But, do some additional research if you really want to extend that puppy. It can be a fun game to play, if nothing else
I just charge it to 95% most of the time and one time per week 100% to balance those battery cells and keep in this 30% to 95% state most of the time it’s been since October 2022 since I bought my iPhone 14 Pro Max with heavy use everyday 10 hours screen time and after all of this now I’m down to 87% battery health and I don’t care to be honest if needed I just replace by battery and that’s it.
I think usage is the biggest factor we can observe here, and in the thread people with higher cycle counts tend to not use the charging limit. But that really just shows that people who use their phone a lot are less likely to use the setting. Temperature is impossible to control for unless you have real device data. But since most people have had the phone close to a full calendar year I think the temperature fluctuations would average out.
iPhone 14 Pro Max here - I abuse my phones battery including leaving it to charge to 100%, auto screen lock off, never use low power mode, 30w fast charge via lightning. I do have optimized battery charging on. My results after two years of heavy usage...
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.
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.
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.
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.
- Current capacity: 87%. Cycles: 329
- Current capacity: 90%. Cycles: 271
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?
Maximum capacity - 88%. So I've lost 12% in two years
I'm at 94% and 520 cycles, using CoconutBattery. On my 14Pro. Up to a year ago, I was still at 103% of original design capacity.
What was my charging strategy? I followed the N=1 experiment I do with charging my Tesla. I charge up to ~60%, as that level is below the 3.92V level where cathodes crack. Look it up. My 6yr old Tesla is still at 100% SOC, so I thought I'd try it with my iPhone.
Since I had to do this manually, it wasn't always possible to stop at 60%, but I was pretty good at it.
And no I'm not religious about it, I would charge as high as necessary if road-tripping my Tesla, and I would accidentally charge my iPhone much higher if I forgot.
This is today's charging, as you can see, I've charged it up to 60% three, now four times in last 24hrs. Whenever I think about it, and am near a charger I'll connect it. Lots of shallow charges.
What was my charging strategy? I followed the N=1 experiment I do with charging my Tesla. I charge up to ~60%, as that level is below the 3.92V level where cathodes crack. Look it up. My 6yr old Tesla is still at 100% SOC, so I thought I'd try it with my iPhone.
Since I had to do this manually, it wasn't always possible to stop at 60%, but I was pretty good at it.
And no I'm not religious about it, I would charge as high as necessary if road-tripping my Tesla, and I would accidentally charge my iPhone much higher if I forgot.
This is today's charging, as you can see, I've charged it up to 60% three, now four times in last 24hrs. Whenever I think about it, and am near a charger I'll connect it. Lots of shallow charges.
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This is the way. I don't understand why you cannot set the capacity to 60%. As close to 50% as possible is best to not strain the battery and 60% is perfect. Moreover, use the slowest wattage charger you can in the evenings, which limits the temperature of the battery and preserves battery.
You can safely charge to 80 or 90%+ on days you really need it and expect to quickly drain the battery. In other words, if it's occasionally only going to sit at 80-90% for a very short while, that's fine.
It’s a tradeoff made necessary by imperfect options. I’m glad to have it, though. I went through 2 batteries in 4 years on my 12 mini possibly because I plug my phone into CarPlay whenever I’m in the car. The constant charging to 100% with no way to stop it seemed to hammer the capacity pretty fast. Setting the capacity to 80% is a minor inconvenience compared to the expense of buying a new car with wireless CarPlay.
I would wait until the battery life sort of craters. That's when you have gotten all you can get out of the battery and its time to replace it.
I picked up my 15 Pro Max at the end of January. Through 205 Charging cycles I am at 95%. I've lost about 3% in the past month or so, call me skeptical but I feel like Apple is still plays games with batteries around new iPhone launch time. But I also do gig work and drive for Lyft and run Door Dash and with a milage app running in the background so I think I am harder on my battery than most.
I recommend people to check the health on coconut battery for expectations. I got a "factory freak" for my launch day 12 Pro. Didn't have to worry about it. One time I started at 100% or just below, that battery was a turd. Hate to say battery lottery, thus why you have big variances in the comparisons and why some folks have their stay at 100% for over a year.
Now I do charge on 5W wired overnight as there is no need of speed. I got 16 Pro now that has like ~24% more capacity than the 12 Pro so get through the day no problem on my usage.
Now I do charge on 5W wired overnight as there is no need of speed. I got 16 Pro now that has like ~24% more capacity than the 12 Pro so get through the day no problem on my usage.
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11 months on my 15 Pro Max. Overnight charging on MagSafe, travel charging USB-C
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.
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.
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.
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.
- Current capacity: 87%. Cycles: 329
- Current capacity: 90%. Cycles: 271
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?
80% charging on regular days, 100% charging on travel/heavy use days
some days I didn’t charge it at all (weekends)
211 charges 96% Max Capacity. 80% charge days have not been an issue.
Manually limiting charge to 80% when possible (short charge session during breakfast since there’s no control for this) has my 14 Pro at 91% since March, 2023. It has spent a fair amount of time sitting at 100% when in the car for long trips (phone playing music) or while using StandBy.
I plan to make use of StandBy much more often with my next phone, so gaining a manual 80% limit option should help tremendously for this use case since sitting at 100% for extended periods accelerates degradation.
Perhaps a factor that explains hit or miss success with charge limits has to do with how long the phone sits at the charge limit. Someone who frequently charges to 100% but doesn’t let the phone sit there won’t see the benefit as much as someone who charges their phone overnight and the phone spends 6 hours plugged in but fully charged. As for a reason why to mess with the charge limiter, it helps with longevity for people who keep their phones until they are no longer supported or those who want to sell their old phone after upgrading (higher battery health helps with resale value). Another situation it helps with is for those that only use 40-50% of the battery between charges in normal use but occasionally need the longest runtime possible, like off-grid excursions, for instance. By trading off runtime when I don’t need it, I’m more likely to have it 2 years down the road if or when I do need it. In my day-to-day, I’m always near power, so going above 75% charge only degrades my hardware and offers no benefit. On occasion, though, I’m away from power sources and then will rely on all of my battery capacity.
I plan to make use of StandBy much more often with my next phone, so gaining a manual 80% limit option should help tremendously for this use case since sitting at 100% for extended periods accelerates degradation.
Perhaps a factor that explains hit or miss success with charge limits has to do with how long the phone sits at the charge limit. Someone who frequently charges to 100% but doesn’t let the phone sit there won’t see the benefit as much as someone who charges their phone overnight and the phone spends 6 hours plugged in but fully charged. As for a reason why to mess with the charge limiter, it helps with longevity for people who keep their phones until they are no longer supported or those who want to sell their old phone after upgrading (higher battery health helps with resale value). Another situation it helps with is for those that only use 40-50% of the battery between charges in normal use but occasionally need the longest runtime possible, like off-grid excursions, for instance. By trading off runtime when I don’t need it, I’m more likely to have it 2 years down the road if or when I do need it. In my day-to-day, I’m always near power, so going above 75% charge only degrades my hardware and offers no benefit. On occasion, though, I’m away from power sources and then will rely on all of my battery capacity.
My phone usually always stays on the charger and it’s almost always on 100 percent
Battery health is 96 percent for the last year.
Battery health is 96 percent for the last year.
I'm on 98% on my 15 Pro, 265 cycle count. I don't limit the charging and it gets charged when I notice it's getting low.
Seriously guys, does it really matter? Is anyone bothered about the battery capacity of their car, or their TV remote? It's a battery, it's not designed to last forever and it makes little difference to the resale value of the phone. Just let it be a battery ffs and stop treating it like a newborn baby.
Seriously guys, does it really matter? Is anyone bothered about the battery capacity of their car, or their TV remote? It's a battery, it's not designed to last forever and it makes little difference to the resale value of the phone. Just let it be a battery ffs and stop treating it like a newborn baby.
@jclo Your experience with this feature is interesting as I've also been wondering what other day-one iPhone 15 customers had for their battery capacities after the first year. Unfortunately I no longer have my 15PM anymore as I had to trade it in for my new 16PM so I can't pull up the exact details, and to be honest I hadn't checked the capacity on it for a month or two before ultimately giving it up to Apple last Friday. However, what I can say is that when last I checked (mid-late July) I was still at a full 100% after putting somewhere between 150-200 cycles through it. I'm sorry I really wish I could recall the exact number but I know it was in that range.
Here are some reference points for context:
Here are some reference points for context:
- I immediately enabled the 80% limit out of the box on launch day last year and never turned it off.
- I would say my wireless to wired charging ratio was more like 70/30 respectively, with much of that wireless charging taking place simply from docking my phone on MagSafe chargers around the house and on my desk at work whether it needed charging or not.
- I didn't often let my phone completely exhaust its charge from 80% down to zero (or close to it like in the single digits) but I did have this happen periodically, say once or twice a month, in a way that was unplanned and my iPhone just happened to be under heavier load from time to time and needed recharging back to "full" (80%). Otherwise I always got through an entire day no problem, if not well into the next day as well.