notebook is a 10 year old macbook pro I installed xubuntu 24.04 in. It comes with an embedded battery.
First notebook I bought, not from apple, had a removable battery. The vendor told me to maximize its life I shouldn’t plug the battery in, unless I need it (like for traveling). This way, I’ve managed to keep the original battery in good working condition for 8 years so far.
Back to the macbook: I cannot remove the battery and constantly loading it to up to 80% and discharge it up to 20% seems ridiculous. Furthermore, this would deplete the battery even faster, I believe.
What can I do to spare the battery as much as possible?
The 80-20 rule only counts for batteries that directly report their state of charge, because they don’t have any logic built in, for instance. Most laptop batteries will have a separate management system that’ll hide the top x% and the bottom y% to prevent over/undercharging, and probably apply some calibration to those numbers as well (because state of charge doesn’t necessarily deplete linearly). However, not going down to 0 and up to 100 does generally save the battery, despite the increased amount of charge cycles, as the most wear is done during deep drain and high charges. Temperature also strongly affects battery lifetime. In practice, very few people actually do the 20-80 thing, though. It’s just too much of a pain manually.
Many modern laptops also tend to have management systems that’ll allow you to pick a minimum/maximum state of charge and let you cycle between them while the cord is connected. I don’t know if Apple implements that, and if it works on Linux, but on windows there’s usually a tool for that. There are also laptops that’ll let you decide on a minimum and maximum percentage, so that the device can charge up to “100%” and drain to “0%” while actually doing 80-20.
I believe most MacBooks have battery management capabilites to set minimum and maximum values. You should check online for details about your laptop’s model and year, there’s probably a tool you can download to configure all that. For instance, there’s this Gnome extension that also had a handy guide for manually setting limits.
The most important part with batteries is to check if they start swelling up. You can have a (badly produced) brand new battery that swells up after one use, or one that’ll work for a decade, it all depends on how lucky you get. With a ten year old laptop, you’re probably already in “can become a lithium balloon” territory.
For linux it depends. For example, you can modify the maximum charge on ASUS laptops. There’s also this wonderful tool called asusctl [https://asus-linux.org/] that modifies allows you to more effectively use your laptop. Here is the arch wiki page for it: https://wiki.archlinux.org/title/ASUS_Linux . Do note that, unfortunately, the only officially supported distros are Arch and Fedora, but you can make it work with some effort.
TLP is my favourite tool for messing with the charge limit. And also far, far too many power/thermal management knobs.
do you mean physically swell up? like I’m going to see it bent/bigger?
Yes, physically getting bigger.
Dell XPS had a batch laptops going crazy and pushing the touchpad up.
You will recognize it :-)
Yes, physically get bigger. A grown battery by itself isn’t necessarily a problem (they’re designed to grow quite big without bursting) but if something pokes through the shell, like for example sharp electronics, compressed hydrogen gas combined with oxidizing metal can escape through the rupture, turning the battery into a portable flamethrower you can’t extinguish with water (without pincking it up, dunking it in water, and leaving it there for a while).
There’s a subreddit about swollen batteries if you want to see some of the more extreme examples: https://old.reddit.com/r/spicypillows/ In older MacBooks, if the battery inflates, it will push apart the frame of the laptop, making the TouchPad unusable and in extreme cases the frame of the laptop will bulge open.
If the battery becomes a problem, you will notice. If you feel like the chassis is starting to bulge, do NOT press down on it to flatten it, but instead take it to a professional so they can take out and perhaps replace the battery. If you want to do it yourself (possible if you’re careful) make sure to look up guides online; there’s a good chance a big bucket of sand and some basic precautions (goggles, gloves, clothes that don’t ignite easily, etc.) is all you need to do this kind of stuff safely. Batteries are quite safe if you’re not deliberately trying to be stupid with them.
This isn’t just MacBooks either; any lithium battery, including the ones in your phone and earbuds, can swell up. It happens most often during charging, when the battery gets hottest inside, which is why you sometimes see ads telling you not to charge your devices overnight.
All of that said: your laptop isn’t a fire bomb, it’s probably fine. Just don’t be stupid around visibly malformed lithium batteries.