iPad Pro 80% Battery Limit worth it?

[Analog Kid]

No, you’re just complicating something that’s not that important. There’s a setting on your iPhones and iPads that makes your battery last longer. It works. That’s all there is to it. That’s what the OP asked - does it make a difference? Yes it does.

That is not what OP asked.

 

[aevan]

That is not what OP asked.

They asked “is it worth it” and the answer is “yes, if your usage allows for it without too much trouble”.

 

[Analog Kid]

They asked “is it worth it” and the answer is “yes, if your usage allows for it without too much trouble”.

“It is worth it if you get more benefit than trouble” is a non-answer, and your attempts to curtail discussion of the benefit side of the equation just further discourages providing the OP information to arrive at their own conclusion.

It works.

How well? Can you give any supportable statement about how much longer one’s battery will last, beyond “conventional wisdom says”?

80% of maximum capacity of the battery that is inside your device. Apple can’t change that, that is a fixed value for each battery.

Unless you can point to an Apple document saying how they define “maximum”, then this is a meaningless statement. And what Apple reports is defined in software, so obviously can be changed (as they did with signal bars).

 

[throAU]

I have recently set the 80% limit for my battery on my iPhone 15 Pro Max, Watch Ultra and my M4 iPad Pro. I have never done this before and although I can still last the day, it takes a bit of getting used to, to not see 100% charged in the morning.

Do you use the 80% limit or not? Do you think it’s worth it?

How long are you planning to keep using this device?

With no limit my larger devices have had >88 percent after 5 years so to me it sounds dumb to sacrifice 20 percent of your run time during the devices usable life, to have a battery with better than 88 percent after 5 years (Macs) when the device is end of life.

iPhones in my experience definitely > 80 percent after 3-4 years with no management.

Personal experience: I have had batteries swell before dropping below 85 percent which means battery replacement anyway.

So my vote: no not really worth it. Make use of the capacity now while you want to use the device!

 

[rkuo]

How long are you planning to keep using this device?

With no limit my larger devices have had >88 percent after 5 years so to me it sounds dumb to sacrifice 20 percent of your run time during the devices usable life, to have a battery with better than 88 percent after 5 years (Macs) when the device is end of life.

iPhones in my experience definitely > 80 percent after 3-4 years with no management.

Personal experience: I have had batteries swell before dropping below 85 percent which means battery replacement anyway.

So my vote: no not really worth it. Make use of the capacity now while you want to use the device!

Limiting the battery charge to 80% prevents the swelling.

 

[LockOn2B]

Wait actually

 

[SpanishAppleNerd]

I have it on. I never use it 100% most of the days anyway, so it's better to have it on. Whenever I need to use it more intensely, I turn the limiter off and that's it.

 

[rkuo]

Limits don’t cause nor prevent swelling, wear and temperature do (barring physical damage). So while it may be true that only charging to 80% reduces wear, it’s only really delaying this. To what extent it does is anyone’s guess.

I’m not clear on what you think “wear” is and how it relates to the battery charge limit, but it is well understood that a high state of charge correlates with battery swelling. Feel free to google it. It’s not “anyone’s guess.”

 

[Isamilis]

I have recently set the 80% limit for my battery on my iPhone 15 Pro Max, Watch Ultra and my M4 iPad Pro. I have never done this before and although I can still last the day, it takes a bit of getting used to, to not see 100% charged in the morning.

Do you use the 80% limit or not? Do you think it’s worth it?

It depends on where you live. If you can get battery replacement easily then it may not be worth. From my experience, there’s no guarantee battery will be longer with 80% limit, due to it also depends on other factors ie, usage, variation during manufacture, manufacture date etc.

 

[aevan]

“It is worth it if you get more benefit than trouble” is a non-answer, and your attempts to curtail discussion of the benefit side of the equation just further discourages providing the OP information to arrive at their own conclusion.

What would you have me say? Give them a lecture about battery chemistry? Ask them to return once they have a degree in engineering?

They asked for advice, this one was mine. It sure feels more useful then your “what is 80% anyway?” response.

Apple put that option there for a reason. They explained what it does and what it’s for. OP asked if it’s worth it and I said that it is, if you don’t mind the hit to the total battery capacity each time you use it. Only OP knows how they use their devices, how often do they replace them (or batteries) so they can decide if they want to turn that feature on.

How well? Can you give any supportable statement about how much longer one’s battery will last, beyond “conventional wisdom says”?

My Mac has 94% battery health after 3 years and my iPhone has 99% health after a year. I’d say it works as this is much better compared to all of my previous Macs and iPhones.

But if you want me to go into battery chemistry, physics and give you lab controlled testing - yeah, no. OP asked for advice, this was mine. Take it or leave it.

Unless you can point to an Apple document saying how they define “maximum”, then this is a meaningless statement. And what Apple reports is defined in software, so obviously can be changed (as they did with signal bars).

And whatever they define the 100% as, this is 4/5 of it.

But honestly, I don’t even need to know what it is. It might as well say “your battery will charge a bit less and be healthy a bit longer”. The important thing is that compared to my previous devices, my current ones have much better battery health after a year (or multiple years in case of my Mac) of use.

OP, you can read my anecdotal case and others and draw conclusions from it or you can read the opinion of this battery scientist here and ponder the relativity of battery measurement (which, yes, is a “guess” at best), battery capacity and life in general. It’s up to you.

 

[digitalcuriosity]

All my iPads in the past and my new Air5 have been connected to charger 24/7 there always 100% as i never take them off charger, and have never had a battery sweel up or fail and i test the system on battery every now and then.

 

[TroyBoy30]

i dont use it. id rather have they extra 20% battery

 

[Analog Kid]

What would you have me say?

You didn't have to say anything-- you injected yourself into a conversation I was having with someone else and told me not to.

It sure feels more useful then your “what is 80% anyway?” response.

Did you happen to read what I was responding to or were you just frustrated that the conversation was happening and you want it all to be straightforward? 80% is not a magic number. You and others keep claiming these things are constants that can't be changed, but an arbitrary percentage of an arbitrary number remains arbitrary.

It is very hard to know what the benefits of affecting one of many variables is in such a complex system. Battery University isn't much help because it's just a hodgepodge of information with few truly useful citations. The plots they show don't even come from the same dataset. It's useful for understanding broad behavior patterns of different batteries, but not useful in answering "what changes if I do something specific with a specific battery".

If you take this BU plot, for example:

it says charging to 100% and discharging to 25% give 4000 cycles before reaching the 80% capacity you've been keeping yourself to all along. That's once a day for 10 years. That wouldn't seem worth it. To be clear though, I don't believe this plot applies to the iPhone battery-- which is why knowing what we're talking about matters.

Apple says iPhone 15 will keep 80% for 1000 cycles, or about 3 years of fully discharging if they're using the standard definition of cycle.

For me, that hardly seems worth artificially limiting myself to 80% and having to think about it all the time.

Apple put that option there for a reason. They explained what it does and what it’s for.

I think it's likely they put it there because people wanted it. Their explanation is much the same as mine has been: "A battery's chemical age results from a complex combination of several factors". You're welcome to tell them not to over think it.

They explain that Optimized Charging is designed to reduce wear, but don't give any indication of by how much. They don't make any claims about the 80% limit, other than that it is there.

OP asked if it’s worth it and I said that it is, if you don’t mind the hit to the total battery capacity each time you use it. Only OP knows how they use their devices, how often do they replace them (or batteries) so they can decide if they want to turn that feature on.

Yes, only they know how they use them. So the information they're seeking is about what setting it to 80% actually does to the battery. They're being told "it will double your cycle life", and "anything with a lithium ion battery should be limited to 80%", or "it's all about heat".

You, for example, said this with such certainty that it almost sounds authoritative:

80% of maximum capacity of the battery that is inside your device. Apple can’t change that, that is a fixed value for each battery.

Here's the iPhone 15 battery labelling:

So what are you claiming is the fixed maximum capacity here? This pack is labeled with two (the second being in the small regulatory text after the Chinese for "Rated Capacity"). Or did you mean the charge capacity rather than the power capacity? It also has two values. It claims the charge voltage is limited to 4.48V, which is strikingly high when most of us are familiar with cells that charge to 4.2V. The numerical differences seem small, but capacity to cycle life changes rapidly at the extremes so we can't just say it doesn't matter.

BU will have us believe that charging above 4.2V gives marginally more capacity for rapidly decreasing cycle life.

The cynical view I'm sure someone here would have is that Apple would do this because they want good specs on the data sheet and they make money from battery replacements or phone upgrades-- but if that's true then why did Apple just raise their cycle life from 500 to 1000 cycles?

My guess is that the battery construction and/or chemistry are different. Apple works closely with their suppliers, often on the basic science and research in addition to manufacturing. So to say it's a fact that Apple can't change is simply wrong. It's also wrong to think we can take data from one place and apply it to another without understanding the differences.


When people make absolute statements, it's worth asking where they get their information from. Most, like you, are drawing strong conclusions from sparse data.

My Mac has 94% battery health after 3 years and my iPhone has 99% health after a year. I’d say it works as this is much better compared to all of my previous Macs and iPhones.

So, with a sample size of one, a different product with a different battery performs better on a health statistic, rather than something useful like run time on a certain task, than some other battery in some other product at a different time and based on memory.

I hope you see how that is the type of situation where people with strong, but unfounded, beliefs might convince themselves of something that may not apply broadly, and why people like me might ask more questions to understand how sure you are of your finding and if this can be aggregated with other anecdotes into a broader trend.

OP, you can read my anecdotal case and others and draw conclusions from it or you can read the opinion of this battery scientist here and ponder the relativity of battery measurement (which, yes, is a “guess” at best), battery capacity and life in general. It’s up to you.

It's good to have your permission.

 

[rkuo]

You didn't have to say anything-- you injected yourself into a conversation I was having with someone else and told me not to.



Did you happen to read what I was responding to or were you just frustrated that the conversation was happening and you want it all to be straightforward? 80% is not a magic number. You and others keep claiming these things are constants that can't be changed, but an arbitrary percentage of an arbitrary number remains arbitrary.

It is very hard to know what the benefits of affecting one of many variables is in such a complex system. Battery University isn't much help because it's just a hodgepodge of information with few truly useful citations. The plots they show don't even come from the same dataset. It's useful for understanding broad behavior patterns of different batteries, but not useful in answering "what changes if I do something specific with a specific battery".

If you take this BU plot, for example:
View attachment 2395382

it says charging to 100% and discharging to 25% give 4000 cycles before reaching the 80% capacity you've been keeping yourself to all along. That's once a day for 10 years. That wouldn't seem worth it. To be clear though, I don't believe this plot applies to the iPhone battery-- which is why knowing what we're talking about matters.

Apple says iPhone 15 will keep 80% for 1000 cycles, or about 3 years of fully discharging if they're using the standard definition of cycle.

For me, that hardly seems worth artificially limiting myself to 80% and having to think about it all the time.



I think it's likely they put it there because people wanted it. Their explanation is much the same as mine has been: "A battery's chemical age results from a complex combination of several factors". You're welcome to tell them not to over think it.

They explain that Optimized Charging is designed to reduce wear, but don't give any indication of by how much. They don't make any claims about the 80% limit, other than that it is there.



Yes, only they know how they use them. So the information they're seeking is about what setting it to 80% actually does to the battery. They're being told "it will double your cycle life", and "anything with a lithium ion battery should be limited to 80%", or "it's all about heat".

You, for example, said this with such certainty that it almost sounds authoritative:


Here's the iPhone 15 battery labelling:
View attachment 2395372

So what are you claiming is the fixed maximum capacity here? This pack is labeled with two (the second being in the small regulatory text after the Chinese for "Rated Capacity"). Or did you mean the charge capacity rather than the power capacity? It also has two values. It claims the charge voltage is limited to 4.48V, which is strikingly high when most of us are familiar with cells that charge to 4.2V. The numerical differences seem small, but capacity to cycle life changes rapidly at the extremes so we can't just say it doesn't matter.

BU will have us believe that charging above 4.2V gives marginally more capacity for rapidly decreasing cycle life.

View attachment 2395378

The cynical view I'm sure someone here would have is that Apple would do this because they want good specs on the data sheet and they make money from battery replacements or phone upgrades-- but if that's true then why did Apple just raise their cycle life from 500 to 1000 cycles?

My guess is that the battery construction and/or chemistry are different. Apple works closely with their suppliers, often on the basic science and research in addition to manufacturing. So to say it's a fact that Apple can't change is simply wrong. It's also wrong to think we can take data from one place and apply it to another without understanding the differences.


When people make absolute statements, it's worth asking where they get their information from. Most, like you, are drawing strong conclusions from sparse data.



So, with a sample size of one, a different product with a different battery performs better on a health statistic, rather than something useful like run time on a certain task, than some other battery in some other product at a different time and based on memory.

I hope you see how that is the type of situation where people with strong, but unfounded, beliefs might convince themselves of something that may not apply broadly, and why people like me might ask more questions to understand how sure you are of your finding and if this can be aggregated with other anecdotes into a broader trend.




It's good to have your permission.

You need to stop with the "there are so many factors that it's unknowable" argument. It's deeply disingenuous and more to the point, simply not true. The effects of shallow cycling and calendar aging at lower states of charge are extremely well understood and easily discoverable if you care about what's actually true and not just arguing. The burden of proof is on you if you are going to suggest otherwise.

 

[Analog Kid]

You need to stop with the "there are so many factors that it's unknowable" argument. It's deeply disingenuous and more to the point, simply not true. The effects of shallow cycling and calendar aging at lower states of charge are extremely well understood and easily discoverable if you care about what's actually true and not just arguing. The burden of proof is on you if you are going to suggest otherwise.

I'm pretty sure the post you replied to included the information you're asking from me, if you wish to discover it rather than just argue.

Does shallow cycling slow chemical aging? Yes it does. But that was not the question. Does it slow it enough to be worth the trouble is the question at hand, and there's very little indication that I can find that it's worth it for many people. If you think otherwise, then please share your easily discoverable source.


There are a lot of people making rather overconfident and certain claims in this thread though. In the conversation you've inserted yourself into, they were that 80% is an important number and that capacity is some fixed quantity. They aren't. I find when people get upset that you're adding information to a discussion that makes black and white more grey, it's because they're not as confident in what they think they know as they want to be.

Do you think 80% is a specific and important number? Do you think "capacity" has one clear and fixed meaning and that Apple is unable to change how they choose to interpret it? If your answer to either of those questions is "no" then I'm not sure why you're concerned that I agree with you.

 

[aevan]

Does shallow cycling slow chemical aging? Yes it does. But that was not the question. Does it slow it enough to be worth the trouble is the question at hand, and there's very little indication that I can find that it's worth it for many people. If you think otherwise, then please share your easily discoverable source.

So Apple randomly put that option?

 

[Analog Kid]

So Apple randomly put that option?

I think they got tired of people obsessively watching Coconut and complaining. The old Apple would have taken a stand and stuck to it. The new Apple is more interested in saying “we hear you”.

Apple just doubled their quoted cycle life to 1000 cycles for iPhone 15. That’s more than enough for me. If my battery usage is low enough that I could use the 80% limit, then 1000 cycles is probably 5 years. I’ve been keeping stuff that long with a 500 cycle limit.

 

[throAU]

Limiting the battery charge to 80% prevents the swelling.

The swelling I’ve seen was at 5-6 years at which point in not using the thing anymore…

 

[throAU]

Also worth noting is that battery degradation happens at the low charge levels too.

If you’re running around 10% more often due to less total charge you may be degrading your battery that way.

Best thing you can do is try keep the phone cooler. Heat kills batteries.

 

[throAU]

Turning a setting on a single time and never having to think about the battery again because you know the phone is just dealing with it in the background is about as far from micromanaging as you can get.

A healthier battery at the non-expense of using the phone exactly as you normally use it is worthwhile for pretty much everybody.

I’ll take not turning a setting on, having 20 percent better life and not worrying about battery health thanks.

 

[RLRabb]

Just an interesting (to me) data point to add:
Three or four months ago I downloaded iMazing and Coconut Battery to my Mac to check the battery health of my M1 iPad Pro (which I purchased new in May 2022). Battery health was reading at about 87%. I checked again around 4 to 6 weeks later (estimate), and the health was then showing at 83%, and a few days later at about 82.5. Based on what I was reading online about best practices, I decided to start manually limiting my charging to about 80-85%, rather than going to 100%, and charging earlier, usually when the battery dropped into the 30s. I started monitoring more frequently, and the battery health has gradually improved. As of today, it is at 88.8% and doesn't appear to have plateaued yet. I'm hoping to get it into the low 90s at least.

 

[aevan]

I think they got tired of people obsessively watching Coconut and complaining. The old Apple would have taken a stand and stuck to it. The new Apple is more interested in saying “we hear you”.

Apple just doubled their quoted cycle life to 1000 cycles for iPhone 15. That’s more than enough for me. If my battery usage is low enough that I could use the 80% limit, then 1000 cycles is probably 5 years. I’ve been keeping stuff that long with a 500 cycle limit.

So basically Apple has been lying all these years and putting optimized charging as the default all these years and now adding manual limitation to everything… because “they hear us”.

Lol. You’re something else.

Anyway, you do you. I’ll keep my devices at the imaginary, relative, ever-changing world of uncertainty that is 80% that not only works according to Apple, but I see the effects of it working. Sorry that I don’t have measurments taken in controlled environments with a control group, verified by a third party. I’ll just have to take Apple at their word.

 

[aevan]

Ah, but that's not what people do, is it? They turn it on, then they post asking if they should have turned it on in the first place. Then they ask if letting their battery go below 20% is ok. Then they ask why it went above 80 percent that one time. Then they ask if wireless charging is ok. And maybe 70% is better than 80% and why can't we set it at 70%? And oh my god my battery life is now 99% and Apple won't replace my battery, should I send an email to Tim Cook?

These are actually valid questions. And whether you should ask them or just don’t think about it is subjective. But, that’s how batteries work currently.

Yeah, 70% limit is actually better than 80%. 40-60 is the ideal range.

Yeah, you should not let it drop below 20-30%

Yeah, wireless charging is worse than wired.

However, not worrying about these things is convenient. And people probably shouldn’t worry about it. But if they do, they should be able to get answers and not be shamed for asking.

 

[Ramchi]

My iPhone 12 Pro Max started degrading after 1 year of use to 84% then after making it 80% Charging level, I could keep the battery at 81% until 2024 Jan I sold it. The actual battery degrades quickly for me to 80s level but after that it stayed longer forever. When I took it to the Apple service for battery replacement, they said 80% is good. I am keeping at 80% level now a days, as my usage is not very heavy now a days.

 

[Analog Kid]

However, not worrying about these things is convenient. And people probably shouldn’t worry about it. But if they do, they should be able to get answers and not be shamed for asking.

Oh, the irony...