Trying to find a good answer (an official from Apple would be nice too!) if leaving my MacBook Pro (m2) connected to power all the time will damage the battery.
I use a KVM switch, which connects my MacBook Pro and Windows PC to my big screen, external keyboard, and mouse. For the Mac to work with the lid closed, it needs to be connected to power. This is the best solution I found to have both computers work at the same time, but I’m open to other suggestions (especially because switching from the PC to the Mac takes a few seconds as it wakes up from hibernation, even though I disabled (I think) sleeping when connecting to power.
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Shay
No, it will not damage the battery. You can leave it plugged in all the time. The battery health features in your MacBook and in macOS manage that. In fact, this will reduce the number of cycles used by the battery and on average the batter will have a longer life.
Just leave it plugged in when power is on-hand and it is convenient and use it on battery when that is more convenient.
Many other people also leave their MacBooks plugged in 100 percent or most of the time as it sits on their desk and is connected to screens and accessories.
I have same question for iPad, and iPhone. On top of this: does the model of either of them make a difference? This "rule" applies for which iOS, MacOS, or model? Thanks
Gustavo: In general, all recent models. I suppose if you are using a laptop or phone from 1998 or 2005 it could be different depending on the specifics. Of course it less convenient to use an iPad or especially an iPhone when plugged in. We don't typically sit at desks and put these devices down on surfaces to use them, unlike laptops. So it is more common to use when not plugged in.
There may have been a change sometime after 2011, because I inadvertently left a 2011 MacBook Pro plugged in for several months without using it, and when I tried it again the battery had swollen up and was completely dead.
BTW, I had the same problem of creating a swollen, dead battery in the first generation Apple Watch by leaving it unused on the induction charger.
Myron: First, yes, lots of changes in both hardware and software over 12 years. But also consider that your battery issue may have had nothing to with it being plugged in. The one time this happened to me it was an unused old 2009 MacBook Air that was NOT plugged in for several months. Temperature variations, and just random luck are the biggest factors.