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MacBook M1 2020 Maximum Capacity
- Thread starter jason95
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False, batteries degrade faster being plugged in always. Even Apple acknowledges this in their battery manuals. Heck, the battery optimization for iPhone was made due to this issues when overnight charging.
Probably good to read this guide to ensure you're taking advantage of all of the options:
If you see Service Recommended on your MacBook Air or MacBook Pro - Apple Support
Learn how to check the health of your battery and resolve charging issues.
There is no formula to take into account battery degradation. Each battery will perform or degrade according to your own usage. Furthermore, how often you charge or your charging habits affect battery health.
Question about that...
I don't have an M1; I have a 2018 MacBook Pro. I leave it plugged in almost all the time. In the menubar, in the tooltip when hovering over the batter, it reads "Charging on Hold (Rarely used on Battery)". I had assumed that means the battery optimization feature of the OS (which I have turned on) allows me to leave the laptop plugged in.
If the OP has this feature turned on, then isn't arche3's comment correct?
P.S. I do move about the house with my laptop, but plug it in when I settle into a spot.
Batteries degrade due to constantly being plugged in, not because they are being charged, but because their internal "juices" or ion-electric materials are not in "motion".
Batteries for portable stuff (like iPhones and Macs) like to have their bits moving. Having them stuck all the time creates a problem called memory charge which means electrons stay stuck to either the anode or cathode. Hence, less moving electrons means less charge per cycle which means less capacity.
This is irregardless of either M1 or Intel.
There is also the issues of battery degradation by having a battery charge all the way up to (at a steady rate) 100% and staying there. Also affects battery health.
Thanks for the explanation. I will say that my battery does slowly discharge when it's in the state I described. Right now it's at 80%. I don't know how the rate of discharge compares to an ideal "motion", but it does eliminate your 100% charge concern.
Apple has changed the charging pattern to charge up to 80% (same as Tesla does with their cars on super charger networks) to extend the battery health. No battery likes to be charged constantly to 100%. It simply degrades it faster.
Furthermore, the extra charge time and speed of charge to get from 80% to 100% is prolonged which in turn means your battery is idling longer than it should which creates the memory charge issue.
Take regular car batteries. They love those fast and quick charge and discharge cycles.
Furthermore, the extra charge time and speed of charge to get from 80% to 100% is prolonged which in turn means your battery is idling longer than it should which creates the memory charge issue.
Take regular car batteries. They love those fast and quick charge and discharge cycles.
Thanks again - great information.
Yesterday my battery was down to the around 73%. Today it charged up to 80% which is consistent with what you said. So, it does seem to be cycling slightly. I guess that's not quite enough based on your input. When I move away from my dock (where it's impossible to keep it discharging) I let it run on battery for a while.
Right. Based on jav6454's input, I would reword their statement from
"batteries degrade faster being plugged in always"
to
"batteries degrade faster when not allowed to discharge"
So, it could be you and jav6454 have no disagreement.