Charge limit failing to stop battery charging

What you might be seeing is actually expected behaviours — not a bug.

On macOS 26  Tahoe, the battery charge limit (80%) only actively works when the system is powered on and macOS can manage charging. 

When your MacBook is shut down completely, the operating system isn’t running.

The charging is handled at a lower firmware level that does not enforce the 80% limit strict

Will not restrict charging to 80% with ne… - Apple Community

magsafe4_creator wrote:

1. Well over time, yes, it will be damaged.

No, as long as the battery is exercised and is never left at 0% charge (or left at less than 5% or kept at 100% all the time), it will remain healthy.

2. If apple put it, it has to work, otherwise, what is beta software for?

Have you even seen recent versions of macOS....especially Tahoe? Full of issues. You are running Beta software for the next OS. Stable product software releases haven't been a thing for years now since Apple & most others feel patching things afterwards is a better way to do things. It also used to be the rule that only major OS releases contained major changes, but these days Apple and others are severely modifying the OS with their minor update patches.

3. If it has to charge to full every once in a while to co-ordinate sensors, let it be a message saying it has to fully charge.

While Apple may not mention it in the Battery System Settings, Apple does mention it in the following article (read it carefully since it contains lots of small details):

About Optimized Battery Charging and Charge Limit on Mac - Apple Support

If you feel Apple should mention these details in the Battery System Settings, then you can provide Apple with product feedback here:

Feedback - macOS - Apple

I don't need that chemical damage out of a failing limit. from now on, i think its me and how it goes. it either works, or doesnt. I think apple really need to fox this. i know it may sound like its not worth the headache, but it actually is when paying around $200 to replace a battery that can be easily kept healthy for longer by not charging to full.

You are overthinking this. Configure the laptop for Optimized Charging and let it go. In fact ignore all battery health details until the battery is no longer working to your satisfaction. Also keep in mind neither Optimized Charing or the Charging Limit will work when the laptop is powered completely off.....so if the power adapter is connected during that time, then the battery will be charged to 100%.

magsafe4_creator wrote:

there is a simpler way than joining the argument (or debate?), just keep it simple: admit apple need to fix this.

done. GAME OVER. its this simple

End users need to admit nothing. If Apple needs to fix something, tell them. They won't see your issue in these user-to-user forums. They WILL see feedback submitted using this:

Product Feedback - Apple

I am hesitant to join this discussion

If the user believes the Limit Charging is not worth it

Consider a Third Party Application call AlDente

Set it once and walk away

https://apphousekitchen.com/?via=phan-lieu&utm_source=review&utm_medium=aitrove&utm_campaign=content&gad_source=1

Personally, on 1 M5 MBA and 1 M4 Laptop both with macOS 26.5.1 Tahoe

I have set the Limits to 90 % and it just works as Apple Designed it to work

It's simply not worth. worrying about. If you obsessively manage your battery, you may gain 2 weeks Moree of usable life. And 81% on an 80% charge limit is within the few percentage indicated in the support article.

Hello 👋

Charge limit is not a perfect feature, sometimes my devices go a bit under from 80% and sometimes a bit over... Charge limit is just an option, even if your Mac goes at 100%, it's not a problem... If Apple added this feature, it's probably because they don't want Mac users to use third party apps...

Btw like Owl-53 says, this feature doesn't work while the Mac is off and I could add that it might also not work in some cases like macOS partitions...

Based on your photo, it appears to be working.

see About Optimized Battery Charging and Charge Limit on Mac - Apple Support

magsafe4_creator wrote:

..seriously...?

it does not work... its on 81%, i unplugged in time...

If it charges to 82%, your battery will be fine.

If it charges to 83%, your battery will be fine.

If it charges to 92%, your battery will be fine.

If it charges to 99%, your battery will be fine.

If it charges to 100%, your battery will be fine.

You are dwelling far too much on an option that might mean a lifespan increase of a few days or a week. Is it really worth the worry?

magsafe4_creator wrote:

there is a simpler way than joining the argument (or debate?), just keep it simple: admit apple need to fix this.

done. GAME OVER. its this simple

Or, you could simply apply logic and realize that any attempt to micromanage the charging process is a complete and utter waste of your time, for little or no benefit.

magsafe4_creator wrote:

Guys, lets calm this down and summarise it. If a limit, or a feature doesn't work, whats the use of it? My laptop isn't ever powered off while charging anyways. Just keep it simple, and just admit apple need this to be fixed, is that a problem? Thanks for your help all of you anyhow. My point is, if my battery charges to full, and stays over 80% for 2 days a week, that is 96 DAYS EVERY YEAR with the battery OVER 80%. The affect of this will never be 2 weeks of extra lifespan.

Thanks to all of you anyways

You seems to worry too much about this... 79, 80, 81 or 82 won't matter... the point is just to not go at 100... Even if it goes above 80%, you won't notice any difference... Just move on, your battery will be fine...

magsafe4_creator wrote:

Thanks for that. this is my only Macbook, and i need it to last as long as possible. I just wanted to understand why it isn't working. you can tell from the original post, i mentioned that "what is the point of something that doesn't work." if someone cant physically fix this, all they had to do is admit it doesn't work. Why do people think its terrible to do that?

Respectfully my friend

As mentioned earlier, the M5 MBA and Charging Limit on this machine with Tahoe 26.5.1

Using these setting, as per the two images below

When I look at the Magsafe Cable

It is showing Orange meaning it is drawing power and will not charge above my choice of 90% charge