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macOS Tahoe 26.4 Adds Slow Charger Indicator for MacBooks
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Yes, and as I said there is not one person who unilaterally makes this decision. It is a team decision and a team makes the change.
You can still have a fall guy, but there is not one person at a company this large who does everything themselves.
Avenged110
macrumors 6502a
Apple's almost as obsessed with completely unnecessary submenus as it is with stupidly over-rounded corner radii.
It is design by a committee that never read the original UX guide. They no longer do usability test like they used to. They rely on metrics collected from use. Yet, they don't know how to interpret the metrics. They just guess at what they mean and point to the numbers as "objective". Yes, the numbers are objective; the interpretation is not. For example, if 90% of users don't change their charging level, what percentage don't know it can be changed, what percentage don't understand why they might want to change it, what percentage don't know how to change it, what percentage can't find the control and give up, and what percentage are happy with the default? I guarantee if you ask questions like this (which I did at Google) you will be considered difficult.
I believe macOS has to be running to know to limit the charging to 80%. I noticed when I updated my iPhone last night, it was charged to 85%. I'm assuming while it was updating, iOS wasn't running to limit the charging so it just charged up.
Now I'm curious about what happens when it hits 80%. Does the macOS go into bypass mode and just power from the charger, leaving the battery to sit there? Is that better for battery life/cycle count? It will still drain but slightly.
These features should have been added to macOS a long time ago
I often charge my MBP with a USB A to USB C cable plugged to the integrated 10W charger on my wall. Works slowly but well.
jchap
macrumors 6502a
Excellent questions. From what I can tell, charging goes into a “steady-state” mode at that time, where the Mac is powered by AC power, and the battery is allowed to drain naturally (very slowly, since there is no power being drawn from the battery at that time), while slightly charging as necessary just enough to hold the specified charge limit.
There must be some kind of mechanism (firmware, etc.) that makes the logical decision when the Mac is powered down as to whether the battery still needs to draw AC power to charge or not. Otherwise, it would charge excessively, which is not good for the battery either.
As to whether that firmware is now controlled by the battery charging limit that the user sets in macOS 26.4 and above, it seems unclear. From what I can tell so far, the Mac just charges fully when it is powered off and connected to AC power, regardless of the limit that the user sets. It’s still a little early to tell, though. Maybe other users can share their experience here.
I also completely shut down my Macs after using them, and shut off the AC power delivered to the machines as well. One user here dogmatically said to stop that habit, without giving any reason, but I don’t see that it causes any harm whatsoever, and it saves a modicum of electricity as well. After all, what is the point of powering a device at all when you’re not using it?
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jchap
macrumors 6502a
Meanwhile Android offers slow charging as a software feature to improve battery longevity. Apple wants you to replace that battery sooner to make more $$$.
dmtworld
macrumors member
Okay, since yesterday I managed to find some stuff from Apple as well as the community here and there. I recommend a full read, but I will pin the relevant for this topic.
So let's start with Apple Official Support:
From "Maximizing Battery Life and Lifespan" scrolling all way down to heading - Store it half-charged when you store it long term. First bullet point.
- Do not fully charge or fully discharge your device’s battery — charge it to around 50%. If you store a device when its battery is fully discharged, the battery could fall into a deep discharge state, which renders it incapable of holding a charge. Conversely, if you store it fully charged for an extended period of time, the battery may lose some capacity, leading to shorter battery life.
- What I would like to know what is "long term storage"? A couple days or months?
From "Change Battery settings on a Mac laptop" under Charging.
- Optimized Battery Charging: To reduce battery aging, have your Mac learn your daily charging routine. Then your Mac delays charging past 80% when it predicts that you’ll be plugged in for an extended period of time, and aims to fully charge the battery before you unplug.
- On Apple Community there's a post (this is before the Tahoe 26.4 patch btw) by Lawrence Finch and Mac Jim ID. They make the same statement, that MacOS has to have time to learn how we charge (which naturally includes when we unplug or plug)
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I saved the last one which from MacPowerUsers. A reply by geoffaire.
"If you follow the advice, it suggests that if you use it regularly connected to a charger (dock or otherwise) it’ll only charge to 80% which would maximise the value of the battery life (versus it being constantly charged to 100%
When they talk about not charging it regularly to 100% they mean doing that then powering it down and leaving it charged to 100% as this damages the battery. If your MacBook is on, macOS will manage this for you."
- Same thread and by geoffaire:
And therefore it seems (but I nevertheless can be wrong here) the answer is: Yes, if most of the time you use MacBook at home, it is best to use it plugged in.
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The MacPowerUsers thread is the ONLY one where I can find that having it shutdown is not a good idea (in terms of charging that is)
Perhaps this is best tradeoff? Shutdown and charging to 100% full will degrade the battery faster versus putting our MacBooks to sleep (yes it still drains a bit battery). The latter is merciful on our batteries compared to the former. I still don't know if the charge limit doesn't work due to being shutdown or MacOS needs more time for it to learn and predict my charging behavior. And can it learn while the MacBook is shutdown?
Curious to hear what you think.
dmtworld
macrumors member
I looked into a bit of it some days back. Look my post above.
Thanks. I set my battery to 80% and it seems to be a hard limit. When I allowed macOS to do what it thought was best, I would see it charge to 100% quite often even though I keep it mostly plugged in. I'm guessing it wouldn't go to bypass often. Now that I set it to 80%, it's pretty much always there. I have seen it dip below 75% but it may have gone to 78%. I turned on battery percent in the menu bar to keep a closer eye on what it does.
From what I've read, if it dips slightly a couple of percent, I'm going to assume it's on battery bypass when it's charged to 80%. This means less battery usage and should prolong its life.
thejadedmonkey
macrumors G3
I've seen this a few times. I don't have a cool Mac so I just have a USB-C cable, so maybe I don't have all the information, but I did have a few MagSafe Macs.
When I glance and see green, I'm expecting a 100% fully charged Mac. If the limit is 80% and I glance, orange will tell me it's not fully charged and I shouldn't grab, go, and expect a long day.
Yeah, that doesn't make sense. Maybe Apple just didn't think that through yet?