I have a 16" M3 Max that I bought close to when it was released. It has been plugged in and in clamshell mode for about a year and a half, other than a few business trips it has been on. I use it all day. The battery health is normal and the max capacity is still 100%. MacOS has been pretty good keeping it at 80%. Might take a day or two when I get home from traveling to figure it out, but that's about it.
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Disadvantage of constantly using clamshell mode?
- Thread starter whwang
- Start date
- Sort by reaction score
Curious. How did you kill the battery in clamshell? I've had my Macbook in clamshell for over a years and have a battery health still over 100% [105% to be exact]
I'm curious about that too. I had one MBP 16 with M1 pro since early 2021 and used with clamshell mode 99% of the time and the battery was still excellent after 3 years of use unstop. At end of last year, I upgraded to a MBP 14 with M4 max and also used it almost exclusively in clamshell mode. So far, the battery was also excellent.
I simply let macOS to handle the battery maitenance. Most of the time, the charge level was kept around 80% top.
At the moment, I'm traveling and using the battery. Here is the battery status.
I wish that was true. I left two new M1 MBAs plugged in for several weeks with no additional software and never saw the Optimise Battery setting limit the charge to 80%. That was back in 2020 and early 2021, so it may have improved since then. I started using AlDente when it became available for Silicon early in 2021 and have always put it straight on MacBooks I have bought since then because I like the extra control and visibility.
Certainly the OBC 80% thing works for many people but at that time I was far from alone in it not working.
If the battery AI learns you're using clamshell mode mostly and keeps your battery at 80% charge then its fine.
The problem comes if the AI keeps charging you to 100% and staying there.
Heat is essentially a non-issue with Apple Silicon...unless you're using a fan-less Mac and editing 8k footage.
The problem comes if the AI keeps charging you to 100% and staying there.
Heat is essentially a non-issue with Apple Silicon...unless you're using a fan-less Mac and editing 8k footage.
Last edited:
Maybe there's some threshold you're not hitting, but it's definitely true.
I have an older relative who literally never unplugs her MacBook Air M2, and every time I remote in to help her with something the battery is not fully charged and is showing the message I described above. So, the OS does do battery management. Maybe not up to the level of the battery hobbyist crowd, but it's definitely there.
Yes possible my usage doesn’t quite fit. I should have said I wish it was true for me. I know it works for many people (and did say that later in my post). It might also be true for me now with latest macOS version. Perhaps I will try it out on my 2020 M1 MBA which I bought second hand a few months ago and is down to 85% battery health, so the horse has already bolted on that one.
It takes several weeks to drop charge to 80 percent if it learns you run on AC all the time.
And even when it does limit charge to 80 percent it doesn't limit it permanently. It learns when you're likely to use the machine on battery and bumps the charge up a bit if it thinks you might need it soon.
Thanks. I had heard about 'several weeks' before, which is why I tried it for two months on my first silicon MBAs.
The description of OBC in Settings and in this Apple article is all about learning daily routines. I don't have a daily routine. My default is always plugged in at home, but I take it away for a weekend once a month or so and in between might use it somewhere else at any time of day. I haven't seen anything written by Apple about Macs which spend most of their life plugged in, but have seen reports (as in this thread) where they are held mostly at 80% charge.
I suspect that there is a no-mans land in between a detectable daily routine and being plugged in 24/7 for extended periods...and that I just fall down the gap.
I have now re-set AlDente to zero control and then uninstalled it completely, rebooted and turned on OBC so will try and hold out for several weeks to see if things have improved since I last tried seriously on Big Sur.
Last edited:
Just as another data point for you, I run my M4 14" MBP in clamshell fulltime, with the exception of three or four times a year taking it on trips. I notice when I get back from my trip and put it back in clamshell mode, it usually takes about two weeks to start limiting charging to 80% again.
I'm guessing if you are using yours on battery for short period in between trips, that may be resetting the clock, so to speak, on the 80% charging.
Battery management has definitely improved since then. I had a 2020 i5 13" MBP that I ran clamshell frequently.
Manually squelched charging from the external display at times to maintain between 20-80% and it did well. I sold it last year while the trade-in value was still decent and offset the cost of upgrading to a used 18 GB Pro M3 14" MBP that has been spectacular.
I had issues with the Battery AI on my M1 Max MBP and consequently my capacity dropped to 87% fairly quickly because it kept charging to 100%. I just to move around the house with it but it was still mostly docked
My M4 Pro MBP however has been much more consistent because it rarely leaves my desk. But when it does, it defaults to 80% again after about 6-10 days.
Never used AlDente
There's a theoretical guide on Apple Discussions on how the Power Management AI works.
It also appears OS updates can disrupt the AI.
I noticed it charges to 100% initially after every OS update and then drops down again which would suggest that a bug in the OS could potentially mess up the algorithm forcing you to start over.
My M4 Pro MBP however has been much more consistent because it rarely leaves my desk. But when it does, it defaults to 80% again after about 6-10 days.
Never used AlDente
There's a theoretical guide on Apple Discussions on how the Power Management AI works.
It also appears OS updates can disrupt the AI.
I noticed it charges to 100% initially after every OS update and then drops down again which would suggest that a bug in the OS could potentially mess up the algorithm forcing you to start over.
Last edited:
The issue isn't necessarily battery health. I've had to replace batteries several times because they expand if they are plugged in too long and much over 80%. It's not as bad now as it was back when the 2015 Macbook Pro (four batteries replaced under applecare) and the 2019 Macbook Pro 16 (two replaced), but sitting at a full charge for long periods is not good.
Optimized charging works great if you are using it away from the desk most of the time. If it just sits on your desk though, it has nothing to learn from. I use Aldente Pro as well, and I have it set to 80%. Then once every couple of weeks it automatically calibrates the battery (80% to 0, then charge to 100%, and finally drain to 80% and hold there).
Agree with the others that have no issues using it in clamshell mode. I use mine that way form Monday-Friday every week, and bring it out on the weekends when my work computer is put away. Never had any issues with it. And with the M series Macs, the laptops rarely even get warm.
Just looking it from an economic perspective, not having to buy a second upgraded machine currently will save you more than you would even spend on any potential repairs. Even if you usually keep your laptops for 10 years and this somehow (it doens't but just for sake of argument) causes your computer to completely die after 5 years, and you bought another of the exact same model, it would still be cheaper because that's now a 5 year old computer you are purchasing, plus you've saved the money (and could theoretically invest it) for those 5 years.
Not to even mention the simplicity of having everything on one computer. I'd do it in a heartbeat.
And FWIW, the battery charging stuff in Mac OS X works well for me. It's on right now, says that charging is on hold (Rarely used on battery). The charging cord shows orange, like it's charging ,not green like it's full) and it's like that all the time.
Just looking it from an economic perspective, not having to buy a second upgraded machine currently will save you more than you would even spend on any potential repairs. Even if you usually keep your laptops for 10 years and this somehow (it doens't but just for sake of argument) causes your computer to completely die after 5 years, and you bought another of the exact same model, it would still be cheaper because that's now a 5 year old computer you are purchasing, plus you've saved the money (and could theoretically invest it) for those 5 years.
Not to even mention the simplicity of having everything on one computer. I'd do it in a heartbeat.
And FWIW, the battery charging stuff in Mac OS X works well for me. It's on right now, says that charging is on hold (Rarely used on battery). The charging cord shows orange, like it's charging ,not green like it's full) and it's like that all the time.
None that I can think of. I have a M4Pro16 (48GB RAM) that has been in clamshell, connected to Studio Display since the day the M4Pro came out. I purchased a couple of the following to hold my computers in clamshell both at home and work:
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.