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by osdril 940 days ago
FYI, on Apple Silicon Apple included a firmware-level "hard-switch" to limit the charge to 75/80% only. It was discovered by marcan while working on Asahi and in my experience it's much more convenient than the built-in ML-based solution (and also less hacky and bloated than AlDente).

See this discussion [0] on GitHub for the explanation and this snippet [1] for easy use.

This solution also works while the laptop is sleeping, the only limitation is that it doesn't survive reboots.

[0] https://github.com/actuallymentor/battery/pull/163

[1] https://github.com/actuallymentor/battery/pull/163#issuecomm...

4 comments

I use the paid version of an app called Al Dente [1] to set the battery charging level to a specific limit. The app has a free mode. It has more features than what I stated, and works on Intel Macs and Apple Silicon Macs (limited only by what the underlying hardware allows).

[1]: https://apphousekitchen.com/

I don't know if they changed this, but I think AlDente follows a polling approach where it periodically checks the charge level and enable/disable the charging accordingly. Such solution is more hacky and it also could cause some sleep-related issues.

The SMC key discovered my marcan is nicer because it enables the same functionality without having to poll anything, as it's built into macOS.

Furthermore, I don't care about all the extra stuff they have put into AlDente, I just want to keep my battery at 80%.

I had such a switch in my old Samsung laptop. Works much better than software-based solutions, which are often simply unreliable.
Subscription pricing eh?
There’s a free version that allows you to limit the charging to a specific level. I found this app useful over the years and I bought the lifetime license when it was on a sale. Otherwise I wouldn’t have paid for it since I don’t like the idea of subscriptions either.
My older intel based macbook pro has started to tell me i use it mostly plugged in and won't charge higher than 80% on its own. There's also a 'charge now' button.

I'm not even on a recent Mac OS, it's still on Monterey. No extra apps to handle battery.

Of course, it doesn't look like a hard limit, but something triggered by usage patterns.

My problem with the built-in charging limiter is that if you are not extremely consistent in your usage patterns (I am not), it basically never kicks in. I much prefer a manual solution.
This is my problem as well. It‘s nice _when_ it kicks in, but too inconsistent.

Why oh why can‘t Apple just add a hard 80% limit switch somewhere in the battery settings. What happened to thinking of nature, guys?

Hmm yeah, I changed my pattern and used the laptop on battery for like a week and the charging only to 80% message is gone.
this switch is available to users on iPhone 15's
I know, I hope Apple will decide to expose it to everyone in the future, since it's already implemented..
It would be very easy to implement in software. Just display a green and yellow/red bar on the battery status icon and allow for people to say full is 80%, empty is 20%. Or something.

For me it is well worth going from charger to charger (they are everywhere, especially if you put some wireless chargers here and there) if that means the phone can still do a full day after 5 years.

I generally use phones until they stop working. I'm into my 3rd year with my iPhone 12 mini, the phone is still super fast, takes great pictures and still feels like "my new phone".

BCLM can set charging thresholds on Intel Macbooks https://github.com/zackelia/bclm
Nice, didn't know that!

Basically the SMC key that marcan discovered is the same thing for Apple Silicon