What should I limit my battery charge level to?

[Fred Zed]

My understanding of batteries is as such that when it’s plugged in at 100% it ain’t bypassing the battery circuit whatsoever. Hence why your battery cycles still increase. I also believe that the current battery management system wears the battery down, it’s bouncing from approx 94 to 100% which is bad for lithium cells.

The software mentioned in this thread is good for one reason only. That’s to maintain less stress on the cells by not charging all the way to the default 100%. As mentioned earlier by another poster, it still trickle charges when it reaches its set value of say 80%. So those that always thought by keeping the MacBook plugged in all day was healthier for the battery got it all so wrong.

 

[BigMcGuire]

My understanding of batteries is as such that when it’s plugged in at 100% it ain’t bypassing the battery circuit whatsoever. Hence why your battery cycles still increase. I also believe that the current battery management system wears the battery down, it’s bouncing from approx 94 to 100% which is bad for lithium cells.

The software mentioned in this thread is good for one reason only. That’s to maintain less stress on the cells by not charging all the way to the default 100%. As mentioned earlier by another poster, it still trickle charges when it reaches its set value of say 80%. So those that always thought by keeping the MacBook plugged in all day was healthier for the battery got it all so wrong.

For iPad and iPhone - yes, correct - no way to bypass the battery circuit. MacBooks will bypass the battery (in a not charging state) and run completely off wall power - though they're designed to bounce back and forth 95-100% to keep the battery from sitting at a full state for too long. The battery health features in recent Mac OS will even drain to 80% and back up.

Those of us who use Charge Limiter - I find my MacBook consuming cycles a lot more frequently than it used to - but I think this is far healthier than sitting at 100% and running off wall power, even if it does 95-100% now and then.

Charge Limiter seems to keep my battery in a trickle charging state almost constantly.

My 2015 MBA had almost no charge cycles because I kept it plugged in all the time even though I used it heavily for 3 years.

My 2017 MBP spends most of its life plugged in but with the charge limiter - I'm eating cycles a lot more than before. Even though I've used the laptop for 28 months heavily (every day for 10+ hours a day basically) I only have 89 cycles.

 

[Fred Zed]

I don't think this is correct. I have been using my charge limiter for over a month and the number of charge cycle does not increase every time it reaches 55% I set on my MBP when plugged in. I don't know how the electronic system is set up for counting the charge cycle, but my guess is it is related to amount of battery drain and full charge.

For example, if it is plugged in all the time, one charge cycle will be when the battery has drained "enough times" to make up 100% (or some arbitrary value like 80% or 90%). So if it is plugged in all the time, it may take a month for the charge count to go up by 1 (as the battery always drains slowly even when plugged in) when the amount of discharge "counted" by the electronic system equals 100% (or some other value).

You are correct about the charge cycles. However the battery is still wearing since power is still going through your battery cells to power the mbp. But at least it’s wearing less since it’s not ever hitting 100%

 

[Fred Zed]

For iPad and iPhone - yes, correct - no way to bypass the battery circuit. MacBooks will bypass the battery (in a not charging state) and run completely off wall power - though they're designed to bounce back and forth 95-100% to keep the battery from sitting at a full state for too long. The battery health features in recent Mac OS will even drain to 80% and back up.

Those of us who use Charge Limiter - I find my MacBook consuming cycles a lot more frequently than it used to - but I think this is far healthier than sitting at 100% and running off wall power, even if it does 95-100% now and then.

Charge Limiter seems to keep my battery in a trickle charging state almost constantly.

My 2015 MBA had almost no charge cycles because I kept it plugged in all the time even though I used it heavily for 3 years.

My 2017 MBP spends most of its life plugged in but with the charge limiter - I'm eating cycles a lot more than before. Even though I've used the laptop for 28 months heavily (every day for 10+ hours a day basically) I only have 89 cycles.

Where is the evidence that shows MacBooks bypass the battery when running of the wall outlet? If that were the case a brand new MacBook would have 1 cycle if never unplugged from a wall outlet. I agree with everything else you mentioned.

 

[BigMcGuire]

Where is the evidence that shows MacBooks bypass the battery when running of the wall outlet? If that were the case a brand new MacBook would have 1 cycle if never unplugged from a wall outlet. I agree with everything else you mentioned.

Yeah I knew you'd ask -

Run a MacBook at full clock speed without a battery

I purchased a broken MacBook (Santa Rosa) from Ebay several month ago. I use it as a media center connected to my home theater. The MacBook was dropped and had a broken screen and a beat up case. It was always the eye sore of my entertainment center. I recently decided to put it in a custom tiny...

forums.macrumors.com

SOLVED: Is it safe to use MacBook Air without the battery? - MacBook Air 11" Mid 2011

First, remove the swollen battery now. It is dangerous for your safety as it could cause a thermal invent which is highly toxic and could wreck your laptop. So be extremely careful and cool down the computer and remove the battery and isolate it in a box with some tapes. You don't want to get...

www.ifixit.com

How to Boot MacBook Pro Without a Battery (Older Models 2006 – 2011)

You may have noticed that sometimes you can not power on and boot a MacBook Pro when it doesn’t have a battery installed. Let’s say you had to remove the battery of an older MacBook Pro…

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Can I run my MacBook Pro on just AC power?

I have a used little MacBook Pro 13 inch Late 2008 5,1 and I was told it needed a battery. It charges, then it doesn't, and it shuts off at the most random times, so the thought occurred to me to t...

apple.stackexchange.com

SOLVED: Will this MacBook Pro boot without a battery? - MacBook Pro 13" Function Keys 2017

Unlike the older Retina models 2015 and older. Apple has changed things quite a lot in the newer USB-C systems. SMC will drop the CPU’s clocking quite low once you take the battery out to the point it won’t be very practical. So I wouldn’t do that. You are between a rock and a hard place ;-{...

www.ifixit.com

Can I use my MacBook Pro without battery - Apple Community

discussions.apple.com

Basically looks like you can remove the battery but Apple will reduce the CPU speed by 1/2 or more to keep it from overpowering the provided electricity.

 

[Fred Zed]

It's from coconut battery screen capture.

View attachment 931738

What change from 6/28 on your chart? Is that when you set the limiter and also kept it plugged in all the time ?

 

[Fred Zed]

Yeah I knew you'd ask -

Run a MacBook at full clock speed without a battery

I purchased a broken MacBook (Santa Rosa) from Ebay several month ago. I use it as a media center connected to my home theater. The MacBook was dropped and had a broken screen and a beat up case. It was always the eye sore of my entertainment center. I recently decided to put it in a custom tiny...

forums.macrumors.com

SOLVED: Is it safe to use MacBook Air without the battery? - MacBook Air 11" Mid 2011

First, remove the swollen battery now. It is dangerous for your safety as it could cause a thermal invent which is highly toxic and could wreck your laptop. So be extremely careful and cool down the computer and remove the battery and isolate it in a box with some tapes. You don't want to get...

www.ifixit.com

How to Boot MacBook Pro Without a Battery (Older Models 2006 – 2011)

You may have noticed that sometimes you can not power on and boot a MacBook Pro when it doesn’t have a battery installed. Let’s say you had to remove the battery of an older MacBook Pro…

osxdaily.com

Can I run my MacBook Pro on just AC power?

I have a used little MacBook Pro 13 inch Late 2008 5,1 and I was told it needed a battery. It charges, then it doesn't, and it shuts off at the most random times, so the thought occurred to me to t...

apple.stackexchange.com

SOLVED: Will this MacBook Pro boot without a battery? - MacBook Pro 13" Function Keys 2017

Unlike the older Retina models 2015 and older. Apple has changed things quite a lot in the newer USB-C systems. SMC will drop the CPU’s clocking quite low once you take the battery out to the point it won’t be very practical. So I wouldn’t do that. You are between a rock and a hard place ;-{...

www.ifixit.com

Can I use my MacBook Pro without battery - Apple Community

discussions.apple.com

Basically looks like you can remove the battery but Apple will reduce the CPU speed by 1/2 or more to keep it from overpowering the provided electricity.

thanks for those links, but those are mentioning about removing the battery physically and running it with AC power. My question was in reference to the mbp bypassing the inbuilt battery when connected to AC which I doubt it does. I believe it trickle charges all the time in that state.

 

[Fred Zed]

I fly RC helis for fun so I’ve played with quite a few lithium batteries throughout the years. Some use big batteries as large as 12 cell lipos running at 52 volts. Anyways, some of my packs I’ve left at 100% all the time as I end up using them almost weekly while others are kept at a 55% charge level most of the time and are only charged when I’m ready to fly. Some packs I charge at 4C which charges the packs very fast and are done in about 20 minutes. Others I charge at 1C which takes over a hour. In my experience, the charge level and number of cycles affects the battery much more than charge rate. Also, heat is a bigger killer depending what the charge level the battery is at. In other words a 100% charged battery will be much more susceptible to damage than a battery at 50%.

From my experience fast charging also generates more heat.

 

[Fred Zed]

1 month + of daily AlDente usage, here is the statistics: (keeping charge level at around 50%, using the mac at least 12 hours per day, or more; Battery temps usually between 32-37C)

View attachment 945538

And for this one month it was charged into the wall AC all of the time ?

 

[BigMcGuire]

thanks for those links, but those are mentioning about removing the battery physically and running it with AC power. My question was in reference to the mbp bypassing the inbuilt battery when connected to AC which I doubt it does. I believe it trickle charges all the time in that state.

Yeah, I agree. I'd like to know for sure too. For example: I see this on my 2017 MBP when I reach 100%.

And coconut battery shows:

So it makes me think it's running 100% off wall current, but <shrug>.

 

[yukari]

MBP does not bypass the battery. It goes through the battery but simply does not charge when plugged in.
[automerge]1601485243[/automerge]

What change from 6/28 on your chart? Is that when you set the limiter and also kept it plugged in all the time ?

Yes, that's when I started using the charge limiter.

 

[Fred Zed]

I have an update on the situation. My understanding is that this is a calibration issue.

Once my MBP shut itself down at 17%. On the next cycle, in the same day, it shut itself down at 13%. On the third cycle, it lasted to 1% and then i started charging it.

So, indeed, it re-calibrated itself and is now functioning correctly. Actually, coconut now shows 100% health as well, up from 97-98% previously, although this varies so much.

I'd say that calibrating should be done more often than we thought, since it IS an actual danger to think you are sitting on 50%, but in reality are in the 20-30% range.

At least 1 cycle weekly could probably keep this from happening, although I am still not entirely sure if loss of calibration has any long-term negative effects and which approach is actually the "very best" for the battery.

Or failing that change the value from 50% to higher values periodically to “exercise” the battery.

 

[Fred Zed]

Yeah I knew you'd ask -

Run a MacBook at full clock speed without a battery

I purchased a broken MacBook (Santa Rosa) from Ebay several month ago. I use it as a media center connected to my home theater. The MacBook was dropped and had a broken screen and a beat up case. It was always the eye sore of my entertainment center. I recently decided to put it in a custom tiny...

forums.macrumors.com

SOLVED: Is it safe to use MacBook Air without the battery? - MacBook Air 11" Mid 2011

First, remove the swollen battery now. It is dangerous for your safety as it could cause a thermal invent which is highly toxic and could wreck your laptop. So be extremely careful and cool down the computer and remove the battery and isolate it in a box with some tapes. You don't want to get...

www.ifixit.com

How to Boot MacBook Pro Without a Battery (Older Models 2006 – 2011)

You may have noticed that sometimes you can not power on and boot a MacBook Pro when it doesn’t have a battery installed. Let’s say you had to remove the battery of an older MacBook Pro…

osxdaily.com

Can I run my MacBook Pro on just AC power?

I have a used little MacBook Pro 13 inch Late 2008 5,1 and I was told it needed a battery. It charges, then it doesn't, and it shuts off at the most random times, so the thought occurred to me to t...

apple.stackexchange.com

SOLVED: Will this MacBook Pro boot without a battery? - MacBook Pro 13" Function Keys 2017

Unlike the older Retina models 2015 and older. Apple has changed things quite a lot in the newer USB-C systems. SMC will drop the CPU’s clocking quite low once you take the battery out to the point it won’t be very practical. So I wouldn’t do that. You are between a rock and a hard place ;-{...

www.ifixit.com

Can I use my MacBook Pro without battery - Apple Community

discussions.apple.com

Basically looks like you can remove the battery but Apple will reduce the CPU speed by 1/2 or more to keep it from overpowering the provided electricity.

So I’ve had mine set to 65% and plugged in last two days. Definitely need to use the existing supplied charger since using the iPad 18W would cause it to keep charging discharging whilst being lightly used. No surprise there. Surprised it still works when the MacBook is turned off completely.

I think I’ll periodically change the Al Dante charge levels to give the cells some work and not just let it stick to one value over time.

 

[BigMcGuire]

So I’ve had mine set to 65% and plugged in last two days. Definitely need to use the existing supplied charger since using the iPad 18W would cause it to keep charging discharging whilst being lightly used. No surprise there. Surprised it still works when the MacBook is turned off completely.

I think I’ll periodically change the Al Dante charge levels to give the cells some work and not just let it stick to one value over time.

Yeah that's what I'm doing. Switching between 55% 85% and sometimes 100%. Yeah those 18W iPhone 11 Pro Max / iPad Pro chargers are tough things!

 

[Hyloba]

This was very interesting to read! I have installed the AlDente app and set it to 60%. Will unplug my cable at night was well. Is there any detailed discussion about battery health for ios devices on this forum? I always keep my phone charging through the night, and I'm not sure if I should be using fast charging or a qi charger.

 

[Broko Fankone]

This was very interesting to read! I have installed the AlDente app and set it to 60%. Will unplug my cable at night was well. Is there any detailed discussion about battery health for ios devices on this forum? I always keep my phone charging through the night, and I'm not sure if I should be using fast charging or a qi charger.

Phones are way better in that regard. My Samsung S8 has had the same battery life for at least 3 years and only now is starting to show signs of wear. I have charged it overnight many times and I always keep fast charging on. Phones emit way less heat as well and heat is what kills laptop batteries the fastest.

 

[theSeb]

I know that people have all these various procedures that they believe they must do to keep their batteries in great condition. I never bother. Sometimes my portable Macs stay on the power adaptor for weeks and even months and sometimes they are left in a cupboard for over a year with a flat battery. It seems to work for me.

These are the results from my two oldest Macs with batteries

85% after 5 years and 82% after 8 years. I am happy with that. However these results do confirm that more cycles is better for the battery and deep cycles (like what the little Macbook has been subject to) are worse.

 

[theSeb]

Where is the evidence that shows MacBooks bypass the battery when running of the wall outlet? If that were the case a brand new MacBook would have 1 cycle if never unplugged from a wall outlet. I agree with everything else you mentioned.

Where is the evidence that it does not? Unless Apple is doing something "magical" and totally different to how every other laptop works, once a battery is charged it does not continue being charged and the power does not "flow through the battery". I don't know where this misconception comes from.

When connected to a charger and the battery is charged your laptop is using the power from the socket directly and your batteries are not being charged and electrical pixies are not being sent through the battery. You can use a laptop without batteries in it and plugged into the socket - it will work. I used a laptop like that for a while when its battery died completely, because I was too busy working to have it sorted out.

The battery however does discharge on its own even when not being used. Depending on the circuitry the battery will be allowed to drop by x % and then charged up again. The charger then notices that the battery is going down and will charge the battery again. These are the cycles that you see.

Do you have portable tools with Lithium ion batteries? If so, then you would have noticed the battery losing charge when you are not using them. That's the same thing.

Running down your laptop every few x days actually creates more unnecessary cycles and wear on the battery. Look at my 2012 MBP numbers. I have never bothered doing anything special with it. I have never specially disconnected it and let it run down to x amount and then charged it up again.

 

[Broko Fankone]

These numbers look really bad when you see the cycle counts. Just saying, it's not an argument that proves you shouldn't worry, it's the other way around Considering the years they've lasted it's not a problem either, though. Imagine how long they could last with proper care.

My cell is at 42 cycles now, still at 100% health. You're supposed to get about 1000 cycles before having to replace a battery.

 

[theSeb]

These numbers look really bad when you see the cycle counts. Just saying, it's not an argument that proves you shouldn't worry, it's the other way around Considering the years they've lasted it's not a problem either, though. Imagine how long they could last with proper care.

My cell is at 42 cycles now, still at 100% health. You're supposed to get about 1000 cycles before having to replace a battery.

I must disagree with your analysis, but ok. I am not going to argue. People can do what they want with their time and their ‘worries’.

 

[Broko Fankone]

For sure they can. My other laptop's battery expanded after 2 years of being plugged in almost always. It was close to thermal runaway before I managed to disconnect it from the motherboard. It could have killed my 3k USD laptop, OR started a fire if I wasn't there to handle it on the spot.

So, you let us worry about whatever we want and you do you.

 

[brianmowrey]

These numbers look really bad when you see the cycle counts.

Cycle count will stop correlating to battery wear if the machine is plugged in all the time. But, that doesn't mean that the battery is aging "faster". Just that the odometer isn't logging all the miles. They are five and eight year old batteries, evidently belonging to machines that have been used heavily. They are in normal condition.

My 2nd Gen 2012 is at 85% original cap. It was very lightly used by previous owner. Not a crumb has ever touched the keyboard. Yet the battery went on aging...

 

[Broko Fankone]

It does mean that it is ageing faster, actually. It's not only ageing, it's being damaged. It is an absolutely bad idea to keep any lion battery at 100% at all times. This is how you get swollen batteries which can then explode and start a fire. I've seen it happen first hand, as I said, and it WOULD have exploded had I not been there to disconnect the laptop from the power source and then open it and disconnect the battery from the motherboard.

I recommend you read up a bit on this topic before coming here to these threads and telling people they shouldn't care about it at all. If you don't want to care - sure, just don't spread this around as it is dangerous. What you are doing is precisely harm. Let people take proper care of their tech and you do whatever you feel is OK for you.

Sitting drained, or at 100% is stressful for a battery. High temperatures are stressful for a battery. Combine these for a long time and get yourself an explosion. I don't care how low the chance is. This happens more often than you would like to think, or admit. Otherwise you wouldn't be claiming what you claim. It didn't happen to you but it can happen to someone else. It's good to consider possibilities outside of your own personal experience.

 

[brianmowrey]

This happens more often than you would like to think, or admit. Otherwise you wouldn't be claiming what you claim.

I am not personally in favor of leaving my machine plugged in all the time. That does not mean, that when an 8 year-old MBP shows over 80 capacity, there is any damage to "admit." It is in normal condition regardless of how it has been managed, and whatever failure was risked by that approach.

 

[Fred Zed]

I know that people have all these various procedures that they believe they must do to keep their batteries in great condition. I never bother. Sometimes my portable Macs stay on the power adaptor for weeks and even months and sometimes they are left in a cupboard for over a year with a flat battery. It seems to work for me.

These are the results from my two oldest Macs with batteries

View attachment 973293
View attachment 973294


85% after 5 years and 82% after 8 years. I am happy with that. However these results do confirm that more cycles is better for the battery and deep cycles (like what the little Macbook has been subject to) are worse.

The good old days, they don't make em like that anymore ( cells )