Has anyone seen this before? I believe the small green thunder means the machine is charging. But then the diagram shows that my M1 MBA was charging between 6 PM and 8 PM, but the battery drained by ~10%. Is that even possible? I am not running anything special.
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.
M1 Macbook Air battery drain when charging
- Thread starter haidexs
- Start date
- Sort by reaction score
What kind of a charger was it being charged with? If it was less than 20W or so and you were pushing the machine hard during that time, what you see could have happened.
I used the Apple 30W charger that comes with the machine. And I was not running any heavy tasks.
Yes, I do. I thought it would stop the machine from charging when getting 80% battery. But does it also make the battery go down to 80% from 100%?
Yes. Over time it will let the battery drain while plugged in to reach the 80% mark. The algorithm used is obscure though. My M1 MacBook Air will sit at ~80% on the charger and then suddenly it will be at or near 100% for days until it decides to kick in again and drain back to about 80%. My MBA is almost always on the charger. I've had it since November 2020 and I have a total of 40 charge cycles.
Thank you for the explanation! Then it is really an obscure algorithm. I thought it would always skip the battery and use the power from the outlet directly when the battery is over 80% and the charger is plugged in.