Old Ultrafine 4K (21.5"), M1 MacBook Air, and Battery health

[neuralengine]

I’ve been using my MacBook Air M1 with the older, now-discontinued version of the LG Ultrafine 4K (the 21.5" one from 2016 or so) and today I noticed that the maximum capacity of the battery is listed at 98%. This computer is about 7 months old and just a few weeks ago the battery capacity was at 100%.

I know that 98% is still pretty good and I also know that we no longer need to actively manage battery health in general, and that specifically, the use case of having the laptop always plugged into an external display with power delivery is supported and should not affect battery life but I’m wondering if using such an old (relatively speaking) display is adversely affecting this battery. Like maybe it doesn’t have whatever smarts present-day chargers have that make it so that it’s safe to keep them constantly plugged in?

I guess my questions are, 1 – are the smart controllers that manage battery health on the computer side or on the charger side or both? and 2 - is using an older generation USB-C monitor with power-delivery potentially adversely affecting the battery health of this computer?

 

[mr_roboto]

1 - Everything responsible for the battery's health is on the computer side. The key phrase is "power delivery" - you shouldn't even think of USB power bricks (or the equivalent built into your monitor) as chargers. They're just DC power supplies; the device receiving power determines what to do with it. USB-C PD is a relatively smart protocol for a DC power supply, in that it lets the two sides negotiate what voltage to operate at, but after that process is done it is just a dumb DC power supply.

2 - No. Your battery is simply aging, as they all do.