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iPhone 12 Pro Does it really shorten a battery’s life leaving it plugged in overnight?
- Thread starter TH55
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Charging to 100% does shorten the life a little. That's why Apple has the optimization option which is supposed to only go to 80% by your use schedule and location. Although it's never worked for me and always goes to 100. Even though I rarely go under 60% at home. But I don't think leaving it overnight will make any real difference if you already let it hit 100%.
Going under 20% is much worse. The lower you let it go the worse it is for the battery. I'd pay more attention to how much you allow it to discharge than how much you charge it.
Going under 20% is much worse. The lower you let it go the worse it is for the battery. I'd pay more attention to how much you allow it to discharge than how much you charge it.
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Apparently it does shorten battery life, since your phone is dropping from 100% to 99% and back to 100% through out the night, so it doesn't overheat the battery.
You end up overworking the battery.
Lithium-ion battery life is usually measured in terms of charge cycles. When an iPhone is left turned on and plugged in for several hours, say, overnight, the battery is continually discharging and charging. This is why Apple created an iOS feature that learns when your phone is typically in active use and restricts charging to time periods when your phone usually is not idle.
So, the repairperson's statement is correct for any device with a Li-ion battery that is not running Apple's charging management function ("Optimized Battery Charging").
So, the repairperson's statement is correct for any device with a Li-ion battery that is not running Apple's charging management function ("Optimized Battery Charging").
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Since optimized battery charging this isn’t the case anymore.
If you are worried about battery life imho buying a new battery after 2 years is less of a burden than dealing with all the charging tips
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My wife rarely uses her phone to the degree I do. She used to let it go dead with her iphone 6s, so we upgraded to the 8. She still leaves it in the charger for days, the same with her apple watch 5 (I got a six so gave her the 5) . Of late I have been taking both off the charger for several hours or most of the day to let the battery run down. Battery health is 95%. Mine is the 8 Plus and I have been considering upgrading , 91% battery but I have had it longer. Probably I will upgrade in the fall when the 13's come out. the 8 plus is a tad large for me now. But with mine, I let it run down and then put it on the charger (watch and phone) before bedtime .Generally the phone is 34% and the watch 60% by then. I do worry about over charging, although there is supposed to be a mechanism to prevent it.
I don't think so, because I have a 2011 MacBook Pro with the battery now just over 2000 cycles and still good for several hours general use. It has spent many, many long hours and sometimes days on end plugged in after it was fully charged. From what I understand, it won't start charging again until the battery drops to a certain level, maybe 90%? And thats going to take a long time because the machine is running off the mains when plugged in. Also, you can't overcharge an Apple battery, the devices are 'smart' enough to actually stop charging at 100%, they don't keep going.
But yes, I work shifts and my phone has 'learned' my very regular charging cycles.
But yes, I work shifts and my phone has 'learned' my very regular charging cycles.
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Why do you say this? I’m constantly under 20% and I really don’t see a negative effect on my battery.
The same 2011 MBP I mentioned above has been down to zero way more times than I could ever count, as in laptop shuts itself off. These batteries are what you call 'deep cycle', meaning they are designed to be fully charged and discharged. It's the lead-acid start battery of your car that gets damaged if you run it dead too often.
I agree with who you quoted. In my experience (at least with iPhones) letting a battery drain down shortens it’s life a lot.
Hmm is this why most iDevices are already charged to 40 to 60% when buying them brand new ?
I tried the "good practices" with battery on my replacement iPhone 8 for nearly a quarter. Never burned the battery to the ground, consciously did not do anything to heat the phone up, even managed to use the phone less (organically, since workload was high). I did this because I wanted to see if my habits are causing the unexpected battery capacity drop in my iPhones. I expect a 100% capacity to not drop to 95% inside a month or two. That's it.
At the end of it, it still was down to nearly 95%. Next, I did not care and used my phone normally thereafter. By normally, I mean this:
- texting (accounting for nearly 90% use [Telegram, Messages])
- light browsing (no YouTube, just text websites, and on Safari only)
- maybe an hour of music at night (streaming, Apple Music)
- some other apps (banks, note-taking, etc.) for a few minutes
This is average daily use. Charging required only once a day, I left it overnight and optimised charging kicked in after a couple days.
And I was still down to 92% in a month or two.
Now, for the longest time (nearly a year), it is stable at 89%. I feel this is low for an Apple battery with my kind of light use. It should have stayed in the 90s. Unless I am mistaken in some way.
At the end of it, it still was down to nearly 95%. Next, I did not care and used my phone normally thereafter. By normally, I mean this:
- texting (accounting for nearly 90% use [Telegram, Messages])
- light browsing (no YouTube, just text websites, and on Safari only)
- maybe an hour of music at night (streaming, Apple Music)
- some other apps (banks, note-taking, etc.) for a few minutes
This is average daily use. Charging required only once a day, I left it overnight and optimised charging kicked in after a couple days.
And I was still down to 92% in a month or two.
Now, for the longest time (nearly a year), it is stable at 89%. I feel this is low for an Apple battery with my kind of light use. It should have stayed in the 90s. Unless I am mistaken in some way.
IF you put your phone in Airplane Mode(wifi off,bluetooth off). i doubt it would shorten battery life. Why? Because it wouldnt even decrease. For example, i have charged my 12 PM to 100% before sleeping. When i wake up its still 100%,thus no battery was actually used,or sort of. I have been doing it a few times since i got my 12 PM(Date of purchase 27 February 2021) and my battery health is still 100% and it can still last me 2 days.
Battery technology is not an exact science. My wife has a 2012 MBP and her battery needed replacement after about 1600 cycles whereas mine went over 2000 cycles and is still useable after being thoroughly abused over the last 10 years. Both SMP batteries, but likely made from raw materials from different suppliers. She got her 1st gen iPhone SE 4 years ago, I got mine 2 years ago. My battery is already starting to show signs of weakness with hers performing better than mine.
Basically, from my experience, when it's your batteries time, it's your batteries time. There is seemingly little you can do to change that.
Basically, from my experience, when it's your batteries time, it's your batteries time. There is seemingly little you can do to change that.
No, but the 50% target is based upon how the battery operates.
In one of the other battery threads, someone posted a YouTube video that explained the charge and discharge process very well. Unfortunately, I can’t find that video. So, hopefully, the following is sufficient.
Technically, yes. Although, it won’t be significant. Typically, the effect will be noticeably harmful if the battery stays at extreme levels (e.g., <= 25% or >= 75%) for weeks or months. The other important fact is at idle an iDevice uses little power, a couple of percent or so overnight. Thus even if you fully charged the iPhone, disconnected it, and left it on the nightstand, the battery would still be at the high pressure levels (i.e., still 90%+) for those overnight hours.
Basically, don’t worry about charging a device overnight.
DISCLAIMER: Not all batteries are the same, some may indeed be more sensitive to certain conditions.
In some instances it can be problematic, though not with an iDevice or most modern or even semi-modern devices. For example, if a lead-acid or Ni-Cd battery is discharged to a very low or zero voltage, special care or actions are required to attempt to “recover” it, otherwise, it won’t accept a charge. The power management units in modern devices and microcontrollers in Li-ion battery packs are designed not to allow a full discharge (despite what the battery meter shows). Additionally, even if that level occurs those chips know how to properly apply charge (i.e., recover the battery).
Some other thoughts about batteries. I'll start with a question: What are batteries for? Storing and delivering electrical power. Yes, storing a battery at 0 or 100% for too long will cause some damage, but also constantly using a battery in a 'normal' way will also wear it out. So yes, I agree there are some things you can do that may well extend the life of a battery, but none of it is guaranteed. Either way, I just use my batteries and don't concern myself too much with how long they may or may not last.
We drive a 2014 Ford Fiesta with auto stop/start, something all modern cars seem to have these days, but it is a function I despise with a passion. Why? Because it wears your start battery (and starter motor) out much, much quicker. Stopping and starting a car several times in a single minute is a problem because that charge is not replaced, and seeing as start batteries are not designed for deep cycles it soon fails. We are still on the original start battery 7 years later, with no signs of weakness, yet, because every single time I get in the car I disable the auto stop/start, which is annoyingly on every time you start. My father in law has a car a few years younger and is already on his 2nd battery. My parents have been through more car batteries than I can count. For the record, I am concerned for the environment, so I will turn the car off myself if it's obvious I'll be standing still for a significant amount of time, otherwise, I let it run. I'm of the opinion the constant replacement of lead-acid batteries is worse for the environment than letting a small modern 3 cylinder petrol engine with catalytic converter run for a few minutes.
Now what about your car battery on extended road trips? Does it over charge? I'd like to think modern car charging systems are 'smart' enough not to do that, as with phones and laptops.
On a side note, I love that I can now charge my M1 MBA with a USB-C cigarette charger in the car, at roughly the same rate as the supplied wall charger
This is something you can't do with a Magsafe device.
We drive a 2014 Ford Fiesta with auto stop/start, something all modern cars seem to have these days, but it is a function I despise with a passion. Why? Because it wears your start battery (and starter motor) out much, much quicker. Stopping and starting a car several times in a single minute is a problem because that charge is not replaced, and seeing as start batteries are not designed for deep cycles it soon fails. We are still on the original start battery 7 years later, with no signs of weakness, yet, because every single time I get in the car I disable the auto stop/start, which is annoyingly on every time you start. My father in law has a car a few years younger and is already on his 2nd battery. My parents have been through more car batteries than I can count. For the record, I am concerned for the environment, so I will turn the car off myself if it's obvious I'll be standing still for a significant amount of time, otherwise, I let it run. I'm of the opinion the constant replacement of lead-acid batteries is worse for the environment than letting a small modern 3 cylinder petrol engine with catalytic converter run for a few minutes.
Now what about your car battery on extended road trips? Does it over charge? I'd like to think modern car charging systems are 'smart' enough not to do that, as with phones and laptops.
On a side note, I love that I can now charge my M1 MBA with a USB-C cigarette charger in the car, at roughly the same rate as the supplied wall charger
This is something you can't do with a Magsafe device.
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It is negligible. Most people will not even be able to tell the difference if they charge overnight or sit and wait for their phone to 100% and unplug at the very moment it does.
Turn on Optimized Charging and live your life man.
Wtf is an m1 mba? Speak English bro.Some other thoughts about batteries. I'll start with a question: What are batteries for? Storing and delivering electrical power. Yes, storing a battery at 0 or 100% for too long will cause some damage, but also constantly using a battery in a 'normal' way will also wear it out. So yes, I agree there are some things you can do that may well extend the life of a battery, but none of it is guaranteed. Either way, I just use my batteries and don't concern myself too much with how long they may or may not last.
We drive a 2014 Ford Fiesta with auto stop/start, something all modern cars seem to have these days, but it is a function I despise with a passion. Why? Because it wears your start battery (and starter motor) out much, much quicker. Stopping and starting a car several times in a single minute is a problem because that charge is not replaced, and seeing as start batteries are not designed for deep cycles it soon fails. We are still on the original start battery 7 years later, with no signs of weakness, yet, because every single time I get in the car I disable the auto stop/start, which is annoyingly on every time you start. My father in law has a car a few years younger and is already on his 2nd battery. My parents have been through more car batteries than I can count. For the record, I am concerned for the environment, so I will turn the car off myself if it's obvious I'll be standing still for a significant amount of time, otherwise, I let it run. I'm of the opinion the constant replacement of lead-acid batteries is worse for the environment than letting a small modern 3 cylinder petrol engine with catalytic converter run for a few minutes.
Now what about your car battery on extended road trips? Does it over charge? I'd like to think modern car charging systems are 'smart' enough not to do that, as with phones and laptops.
On a side note, I love that I can now charge my M1 MBA with a USB-C cigarette charger in the car, at roughly the same rate as the supplied wall charger
I used to worry about battery problems from over charging, and then I realised there are more important things in life to worry about.
If I remember correctly, if certain conditions are met apple will replace the battery for free, someone with more info can add further info.
Thanks
If I remember correctly, if certain conditions are met apple will replace the battery for free, someone with more info can add further info.
Thanks
be warned. I attempted to replace my battery and Apple sent it back to me without replacing the battery because they said there were other problems in my phone. I have kept my phone in great condition and there is/was nothing noticeably wrong with it other than the battery degrading. I only sent it in for “repair” because I wanted to prolong the life of the device.
I do consciously try to keep the charge above 20%, but I don’t worry about it too much if it goes below. I just use my phone how I want and don’t concern myself. I’m over 3 years in with my phone and even without a new battery I get most of the day out of it (depending on usage for the day). I do often leave it plugged in over night because that’s when it’s drained and convenient for me.
Anyway... just beware that (especially if you don’t have AppleCare+) there are risks with assuming you can simply replace the battery. Both cost risks and other. Apple not only didn’t replace my battery, they sent it back with my FaceID broken and refuse to fix what they broke. The front camera works, but I can no longer use FaceID for anything. If you plan to replace the battery, do it while under warranty and/or as early as is reasonable. Maybe just before the 2 year mark.
Although I don’t notice any issues with my phone (other than Apple breaking my FaceID), Apple’s diagnostics found something. This is likely because as the battery degrades, it has the opportunity to fry components in your phone as the software/firmware begins to struggle to keep up with the dynamics of the failing battery.
I do consciously try to keep the charge above 20%, but I don’t worry about it too much if it goes below. I just use my phone how I want and don’t concern myself. I’m over 3 years in with my phone and even without a new battery I get most of the day out of it (depending on usage for the day). I do often leave it plugged in over night because that’s when it’s drained and convenient for me.
Anyway... just beware that (especially if you don’t have AppleCare+) there are risks with assuming you can simply replace the battery. Both cost risks and other. Apple not only didn’t replace my battery, they sent it back with my FaceID broken and refuse to fix what they broke. The front camera works, but I can no longer use FaceID for anything. If you plan to replace the battery, do it while under warranty and/or as early as is reasonable. Maybe just before the 2 year mark.
Although I don’t notice any issues with my phone (other than Apple breaking my FaceID), Apple’s diagnostics found something. This is likely because as the battery degrades, it has the opportunity to fry components in your phone as the software/firmware begins to struggle to keep up with the dynamics of the failing battery.
Umm, LOL, I got that from this very forum, bro. MacBook Air. The M1 refers to the new chip made by Apple themselves, ever heard of it? So yea, we tend to talk about MacBook Air's quite often in a forum dedicated to everything Apple and don't feel like spelling it out every time. For the record, MBP refers to a MacBook Pro.
Don't worry, I know exactly what WTF stands for.
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I'm an electrical engineer with some experience with lithium, nickel cadmium, nickel metal hydride cells.
With Li-Ion (or really Li-Polymer in your iPhone) with the latest versions of iOS it's totally safe. They learn your charging pattern (when you sleep) and charge up to 80% quickly and hold it there until just before you wake where it will charge the last 20%. That way the phone minimized the length of time the battery will spend above 80% which over years and years of use can really add up, a small change that will probably provide a considerable boost to cell life. Basically 5 or so hours each day less the cell spends at 100% x perhaps over 1000 days is a lot of wear saved.
Most of the damage done to cells is <20% and >80%. The closer you are to 0% or 100% the more you are causing chemical damage (like dendrite formation) to the cell. Of course number of cycles is a thing too. Ideally you'd keep a battery permanently charged at 50% at perfect operating temperature but that isn't realistic.
TL
R if you are on the latest iOS just put it on charge when you go to sleep, the phone will take care of the rest and avoid running it down below 10% as much as possible.