I suggest not posting untruths. So you’re saying it matters not what you do? Will a battery that sits in a hot car all the time last just as long as one that is at room temperature and doesn’t spend the majority of it’s time at full charge?
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How to limit the maximum charge to 70%?
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I suggest not posting untruths. So you’re saying it matters not what you do? Will a battery that sits in a hot car all the time last just as long as one that is at room temperature and doesn’t spend the majority of it’s time at full charge?
I think the guy is saying that peoples' time is better spent actually using their devices, rather than obsessing over the precise way they should use their device. Most of the time, people get rid of a device long before its battery is worn out anyway.
Also, it goes without saying you should follow normal precautions as described by Apple, IE not leaving your laptop in a hot vehicle and so on. Other than that, don't worry so much. These things are designed to be used by regular people without expert knowledge. ...Well, except for the butterfly keyboard, I mean.
Bottom line we cannot control the battery percentage where charging stop. If we could it would be better for battery life.
Some EVs (like Tesla) do allow setting this upper limit. I set mine to 80% and try to never let the car drop below 30% charge. This gives me a 120+ mile range per day, which is way more than I need. When I do long trips I will charge to 95% and deal with regenerative braking power reduction until 92%.
Some EVs (like Tesla) do allow setting this upper limit. I set mine to 80% and try to never let the car drop below 30% charge. This gives me a 120+ mile range per day, which is way more than I need. When I do long trips I will charge to 95% and deal with regenerative braking power reduction until 92%.
And I suggest letting a 2+ year old die out instead of beating a dead horse? I also suggest not putting words in people's mouths. Where was storage temperature ever brought up before my post? Oh right, it wasn't.
I am talking about the specific situation of limiting the charge to 70% to baby your battery. The time spent on that venture, if you value your time at all, will not ever be repaid by the extra life given to your battery before it needs a replacement. Furthermore, if you DO find a way to do it, the one time you'll need the full battery life, you'll only have 70% available because you took the decision of limiting it. Hence, I suggested OP find a better, more valuable use of their time.
S
I know This is an old thread but there is an easy way to achieve a cut off when it reaches 80% or whatever percentage you desire.
I just bought a USB multimeter tester to check my cables and power adapters. It is a simple pass trough tester with a male usb on one end and female usb on the other. You put this in between your phone and charger on your usb cable. Along with capacity It’s intention is to show you real time volts and amps that are being drawn from the charger to your device(phone).
Since your phone does not charge at a constant rate. To keep it simple, with minimal applications running, your phone pulls more power to charge when it’s at 5% than when it’s at 90%. A Graph would look like a curve from a fast high amp charge when at 5% and a slow low amp charge when it’s near full. the reason the charging speed/amps slows is to protect your battery from overheating and over charging. Think of it like filling a glass with a pitcher. You pour fast when it’s empty and then slow down to a trickle when it’s near full. You do this so you don’t over fill it. The same thing happens when charging your phone, your phone. 0-90% is fast and then it slows down the draw of current when it reaches 80-90%. The last 10-20% is very very slow.
So... one of the protection features is ‘under-current delay time protection’. That means it will cut off power when the charging slows down When it reaches 80%. I have mine set at 0.45a for 1 constant minute (depends on your set up). So after it hits this charge speed it cuts power to my phone. It may not be exactly 80% but it will be close to that each time. As long as you set it correctly. of course if you are using your phone while it’s charging this may change, this is because your phone will pull more amps to accommodate the increase in power loss during usage. As long as you leave your phone alone it will shut of the supply of current around the same % each time.
With the usb multimeter it’s easy to know what the current cutoff should be set to . This also prevents your phone from receiving a continuous trickle charge if you leave it plugged in at 100%.
Link to the multimeter if interested. I am a novice to these things but I find it to be very useful.
https://www.amazon.com/DROK-Protector-Multimeter-Capacitance-Thermometer/dp/B017SOXP1Q/
I know This is an old thread but there is an easy way to achieve a cut off when it reaches 80% or whatever percentage you desire.
I just bought a USB multimeter tester to check my cables and power adapters. It is a simple pass trough tester with a male usb on one end and female usb on the other. You put this in between your phone and charger on your usb cable. Along with capacity It’s intention is to show you real time volts and amps that are being drawn from the charger to your device(phone).
Since your phone does not charge at a constant rate. To keep it simple, with minimal applications running, your phone pulls more power to charge when it’s at 5% than when it’s at 90%. A Graph would look like a curve from a fast high amp charge when at 5% and a slow low amp charge when it’s near full. the reason the charging speed/amps slows is to protect your battery from overheating and over charging. Think of it like filling a glass with a pitcher. You pour fast when it’s empty and then slow down to a trickle when it’s near full. You do this so you don’t over fill it. The same thing happens when charging your phone, your phone. 0-90% is fast and then it slows down the draw of current when it reaches 80-90%. The last 10-20% is very very slow.
So... one of the protection features is ‘under-current delay time protection’. That means it will cut off power when the charging slows down When it reaches 80%. I have mine set at 0.45a for 1 constant minute (depends on your set up). So after it hits this charge speed it cuts power to my phone. It may not be exactly 80% but it will be close to that each time. As long as you set it correctly. of course if you are using your phone while it’s charging this may change, this is because your phone will pull more amps to accommodate the increase in power loss during usage. As long as you leave your phone alone it will shut of the supply of current around the same % each time.
With the usb multimeter it’s easy to know what the current cutoff should be set to . This also prevents your phone from receiving a continuous trickle charge if you leave it plugged in at 100%.
Link to the multimeter if interested. I am a novice to these things but I find it to be very useful.
https://www.amazon.com/DROK-Protector-Multimeter-Capacitance-Thermometer/dp/B017SOXP1Q/
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That's a really cool device! Thanks for the link.
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Xcurrent93 This is a very old thread. I was not aware that type of device existed. Unfortunately that device, or a USB C version, wouldn't work if you had multiple charging types. I use a USB C hub and turning off the hub wouldn't be a useful solution XD
Looking though this tread again though is somewhat frustrating. There are plenty of people invested in discrediting the original question and less interested in answering it.
I for one don't believe that a software solution isn't impossible. Maybe not easy, but surely not impossible.
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It should be mentioned that it seems that running Windows on the MacBook is very detrimental to the battery health. It would be great to hear other people experiences with regards to running Windows and MacBook battery life.
The battery topic becomes somewhat important as older MacBooks become vintage with no chance of buying an original battery. Which is a pity as my late 2008 aluminum unibody MacBook is great at running Mojave and basic consumer tasks.
The battery topic becomes somewhat important as older MacBooks become vintage with no chance of buying an original battery. Which is a pity as my late 2008 aluminum unibody MacBook is great at running Mojave and basic consumer tasks.
I wouldn’t think it impossible either. Lenovo does it through their Lenovo Vantage App, where you can set charging thresholds for your device. Both the minimum charge before it will start to recharge and the maximum charge for where it stops charging.
I used to set the start charging number to 40% and the stop charging to 80% so that it wouldn’t try to top it off every time it was moved from one location to another and wouldn’t charge beyond 80%
Hm - looks rather exceptional. Mine degraded WAY faster. And Apple never did anything on it despite AppleCare and having the MBP frequently with them (Radeongate). Would be great to have a sw that would regulate charging (e.g. keep at 70% +/- something, as the OP requested).
I'd like to chime in to this request - does anyone know of a - preferably software - solution to limit the maximum charge on a MacBook Pro?
I've made some eye-opening observations in the past when comparing my devices undergoing my charging habits ('babying' the battery) to those of other persons in the family. What can I say - my batteries working perfectly fine with no noticeable degradation versus bloated batteries, batteries that would deplete dramatically fast or devices that shut themselves off when still at ~40% charge.
What I did?
- Charge them to around 80% (or to 100%, if I wasn't sure of my next charging opportunity), then disconnecting (vs. leaving them on AC overnight)
- Not using fast charging - the Apple 5W brick is just fine for iPhones (vs. always using fast chargers)
- Charging while using the devices heavily, thus reducing the drain from the battery and reducing charge cycles (e.g. connecting the charger when updating a lot of apps, when doing long phone calls or when navigating with the display constantly on) (vs. letting the battery do the heavy lifting, using up unnecessary charge cycles)
- Avoiding SOCs below 20% (vs. discharging devices until they shut themselves down)
Now I'm looking for a software solution for my MBP 15" 2018, because maintaining a battery-friendly charging experience is really inconvenient without.
The Asus ZenBook of a friend comes with a nice piece of system software which lets you limit the maximum charge to 60, 80 or 100%. I'd really appreciate if there was something similar available on Mac, because I'm certainly not going back to windows just because of battery management software
Currently I am using lower-powered bricks to being able to keep the charger connected longer before reaching a high SOC, reducing battery temperatures and charge cycles (18W is sufficient for light duties, still charging the battery (slowly) most of the time; 30W is sufficient for heavier workloads like running VMs; 60W will almost always charge the battery, even in high-load scenarios; I barely use the 87W-charger, as it is cooking the battery with it's fast charging despite it not being necessary).
The people who will now tell me to do something better with my time: did you even think once of the hassles involved with a battery service? The appointment at a Genius Bar that has to fit into your schedule? The perhaps hour-long drive? The costs associated around it, not only the charge paid to Apple? Having to schedule with your employer? Perhaps sending the MacBook in, not being able to use it for at least a couple of days?
Why should a knowledgeable user NOT try to avoid this, if there's not much more involved than making a few clicks? I don't get THAT...
TLDR: Is there a solution out there to limit the SOC to ~80%?
The only solution right now is available for Macbooks that use magsafe chargers. If you put a thin piece of tape over the middle pin, you will be able to have the macbook run off AC power and keep the battery charge stable.
Doing it now and I've been sitting at 71% battery for the past 5 hours.
As for there being a software solution, that is only possible if the hardware exists to cut off power to the battery. The other laptops that have a software solution to limit charge have circuitry to divert power. I don't think Macbooks have this circuitry, though I hope I'm wrong.
Finally people who get it. Others here don’t give a bleep, like to get new ones every year, or take everything that apple says as gospel. I’ve seen the same thing in my devices. Since 2008 my partners apple devices battery lifespan is much worse than mine. The difference is that I try to do what you posted above while they run their batteries down to 0% and charge overnight to 100% which is harmful to lipos. There’s a reason why your $100,000 Tesla allows you to limit max charge.
Yeah, I've heard of this hack for MagSafe-Adapters, but I've got a late 2018 here - hence USB-C...
I don't think that there really is special circuitry involved for limiting charging - probably it's just an Apple thing again to not let anybody tinker with OS duties. Just like on iOS, where no developer gets access to low-level system properties.
But perhaps there are some smart guys out there who can figure something out nevertheless.
The USB-C-Adapter which stops power when the current falls below a certain level isn't suited for our purpose because it would resume charging if there is some system load.
Perhaps one could invent a USB-C device that gets the "current current" from the OS (third-party monitoring tools can already do that within MacOS) and adjust the current coming from USB-C accordingly?
I don't think that there really is special circuitry involved for limiting charging - probably it's just an Apple thing again to not let anybody tinker with OS duties. Just like on iOS, where no developer gets access to low-level system properties.
But perhaps there are some smart guys out there who can figure something out nevertheless.
The USB-C-Adapter which stops power when the current falls below a certain level isn't suited for our purpose because it would resume charging if there is some system load.
Perhaps one could invent a USB-C device that gets the "current current" from the OS (third-party monitoring tools can already do that within MacOS) and adjust the current coming from USB-C accordingly?
My MacBook Pro 2018 is most of the time connected to an external display via USB-C. Thus, the battery is charged and hold at 100 % soc. Unfortunately, as already mentioned in this thread, a li-ion battery ages at 100 % faster than at for example 80 % soc.
This article https://www.apple.com/batteries/maximizing-performance/ states:
"Software may limit charging above 80% when the recommended battery temperatures are exceeded."
Unfortunately, the devices implementing this are not stated. Probably not MacBooks. But at least it seems to be possible to limit charging to 80 % soc.
What about giving feedback to Apple about this and requesting such a feature?
Best regards,
Fabian
This article https://www.apple.com/batteries/maximizing-performance/ states:
"Software may limit charging above 80% when the recommended battery temperatures are exceeded."
Unfortunately, the devices implementing this are not stated. Probably not MacBooks. But at least it seems to be possible to limit charging to 80 % soc.
What about giving feedback to Apple about this and requesting such a feature?
Best regards,
Fabian
It is a fact that not charging a li-ion battery over certain percentage will preserve its lifetime. Tesla, which happens to be one of the larger battery manufacturers in the world, lets you charge your car only up to 90% (probably even lower, not sure - don't own one) in order to preserve its longevity. How it works - the battery is under greatest stress when fully charged. You can think of one full discharge-charge cycle as of 1 full cycle. If you discharge your battery and then only charge it up to 90%, the numbers don't go down linearly. It would be, say, 0.75 cycle. If you take it further and only charge up to 80%, you'd only stress the battery with 0.4 cycle (please note - I'm making the numbers up, I don't know the exact figures and they will differ with each battery, but I'm doing so to illustrate how the battery charge cycles work).
Knowing this - I too wish that there would be an option to restrict max charge percentage in macbooks. And while I'm not going to be obsessing about pulling the charger out of my mac when it reaches 90% every single time, I will watch it from time to time when I know I don't need a full charge right now. For all those who don't understand/care, that's fine, just don't hate on others who actually think about taking better care of their stuff.
Knowing this - I too wish that there would be an option to restrict max charge percentage in macbooks. And while I'm not going to be obsessing about pulling the charger out of my mac when it reaches 90% every single time, I will watch it from time to time when I know I don't need a full charge right now. For all those who don't understand/care, that's fine, just don't hate on others who actually think about taking better care of their stuff.
In my experience, running Windows on your MacBook will destroy your battery much faster than charging it to a 100% ever will. There is obviously much more at play here than just overcharging.
iOS 13 has smart charging:
"As a continuation of its efforts to improve iPhone battery health and longevity, Apple has added a new “Optimized Battery Charging” option. Apple says that your iPhone will “learn from your daily charging routine so it can wait to finish charging past 80% until you need to use it.”
To access this option, go to Settings > Battery > Battery Health and toggle the “Optimized Battery Charging” feature. For instance, when charging overnight, your iPhone might wait until 2 hours before you wake up to finish charging from 80% to 100%." - 9to5mac
Also, can someone pls try using https://www.amazon.co.uk/AnyWatt-Magsafe-Adapter-MacBook-Laptop/dp/B07CR7JYTS in combination with the magsafe cover hack?) Thanks.
"As a continuation of its efforts to improve iPhone battery health and longevity, Apple has added a new “Optimized Battery Charging” option. Apple says that your iPhone will “learn from your daily charging routine so it can wait to finish charging past 80% until you need to use it.”
To access this option, go to Settings > Battery > Battery Health and toggle the “Optimized Battery Charging” feature. For instance, when charging overnight, your iPhone might wait until 2 hours before you wake up to finish charging from 80% to 100%." - 9to5mac
Also, can someone pls try using https://www.amazon.co.uk/AnyWatt-Magsafe-Adapter-MacBook-Laptop/dp/B07CR7JYTS in combination with the magsafe cover hack?
) Thanks.
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That pretty much confirms what we've thought and the naysayers who continue to claim it makes no difference to continually keep a lipo battery charged at 100% makes no difference to battery life. The same probably even drive Teslas which do have the 80% threshold in mind.iOS 13 has smart charging:
"As a continuation of its efforts to improve iPhone battery health and longevity, Apple has added a new “Optimized Battery Charging” option. Apple says that your iPhone will “learn from your daily charging routine so it can wait to finish charging past 80% until you need to use it.”
To access this option, go to Settings > Battery > Battery Health and toggle the “Optimized Battery Charging” feature. For instance, when charging overnight, your iPhone might wait until 2 hours before you wake up to finish charging from 80% to 100%." - 9to5mac
Also, can someone pls try using https://www.amazon.co.uk/AnyWatt-Magsafe-Adapter-MacBook-Laptop/dp/B07CR7JYTS in combination with the magsafe cover hack?
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
Great discussion! Lots of useful information.
I'd like to share my experience.
I've got a mid-2012 11" MacBook Air. Spends 99% of its lifetime on AC power 24/7.
Mostly light workloads (web surfing, iTunes music playback and a bunch of other programs that mostly sit in background and create no significant CPU or I/O load).
It literally exported under 5 small iMovie projects in the past 8 years of service and that was by far the heaviest workload it experienced.
Went through a couple really hot summers (not Australia hot summers, though). Fullscreen 1080p YouTube videos stuttering hot summers. Or maybe that was bumpy road to HTML5 in Google Chrome.
Anyway, 5 years into the service, battery swelled like crazy.
Gradually, slowly they started to deform aluminium case to the point when the lid wouldn't close tight and keyboard started to look and feel swollen as well.
Never thought it was a thing. Didn't know much about Li-Ion batteries, though.
Additionally, it has never been cleaned in those 5 years.
I didn't babysit the battery. I didn't bother to clean it. Otherwise, I didn't overheat it and tried to use it sparingly in terms of throwing heavy loads at it and subjecting to detrimental ambient temperatures.
Shortly after the battery was replaced CPU fan went out.
Personally, I don't care much about reduced capacity as I know I'm going to use it 99% of the time on AC power. If it can hold out for about an hour on a battery once in a while that's all I need.
However, what I do care about is whether my batteries will get bloated and break other components in my MacBook or, you know, set my place on fire when I'm sleeping.
You're not alone. Same experience here.
Well, glad it worked out better for you! In my case it nearly destroyed my favorite little MacBook
Curiously, in my particular case, I never saw the "Service Battery" warning. All looked normal but the battery still swelled badly.
I'd like to share my experience.
I've got a mid-2012 11" MacBook Air. Spends 99% of its lifetime on AC power 24/7.
Mostly light workloads (web surfing, iTunes music playback and a bunch of other programs that mostly sit in background and create no significant CPU or I/O load).
It literally exported under 5 small iMovie projects in the past 8 years of service and that was by far the heaviest workload it experienced.
Went through a couple really hot summers (not Australia hot summers, though). Fullscreen 1080p YouTube videos stuttering hot summers. Or maybe that was bumpy road to HTML5 in Google Chrome.
Anyway, 5 years into the service, battery swelled like crazy.
Gradually, slowly they started to deform aluminium case to the point when the lid wouldn't close tight and keyboard started to look and feel swollen as well.
Never thought it was a thing. Didn't know much about Li-Ion batteries, though.
Additionally, it has never been cleaned in those 5 years.
I didn't babysit the battery. I didn't bother to clean it. Otherwise, I didn't overheat it and tried to use it sparingly in terms of throwing heavy loads at it and subjecting to detrimental ambient temperatures.
Shortly after the battery was replaced CPU fan went out.
Personally, I don't care much about reduced capacity as I know I'm going to use it 99% of the time on AC power. If it can hold out for about an hour on a battery once in a while that's all I need.
However, what I do care about is whether my batteries will get bloated and break other components in my MacBook or, you know, set my place on fire when I'm sleeping.
You're not alone. Same experience here.
Well, glad it worked out better for you! In my case it nearly destroyed my favorite little MacBook
Curiously, in my particular case, I never saw the "Service Battery" warning. All looked normal but the battery still swelled badly.
Understood... the problem with these stories is we don't really have any way of knowing what caused the problem. Like in your case, how do we know if your battery outcome would have been any different had you not continually charged the battery. It is just so hard to tell what is up with a sample size of one.Well, glad it worked out better for you! In my case it nearly destroyed my favorite little MacBook
I recall in one of the keyboard threads, someone said they managed something like 200 of the newer MacBook Pros at their place of business, and around 40% of them had been returned for KB problems. So when I read that it makes we think... yeah there is a real keyboard problem with these things.
It would be interesting to hear from someone who manages a large number of Mac portables who could provide battery life stats both with and without continuous charging.
People tend to over complicate things. Battery is like muscles, it MUST be exercised. If you lie in bed without a movement for 5 years, you are not going to be in better shape than your bloated battery. The 70% theory maybe correct but in practical therms it is useless. For instance an original Apple battery A1322 has proved to last about 10 years with around 2500 charge cycles and about 80% health. Do you really need a better performance than this?
There is quite a bit of technical research on swelling of battery packs out there. It is a common phenomena and is inherent in the design of Li-Ion batterie pouches. Over time waste products from charging builds up. These allows the formation of gases and dendrites between the anode and cathode. The gases are flammable.
For some basic information see https://batteryuniversity.com/learn/archive/pouch_cell_small_but_not_trouble_free