MacBook Air M2 losing 1% of Battery Health every few days

[colonel179]

I noticed something that has me worried. I checked the battery health like a month ago and it was at 94%. I purchased this Mac on October 2022.

However, I checked it again after a few days and it was at 90%

I've been checking the battery health regularly and it keeps dropping. Today it is at 87%.

I called Apple support (or authorized service centre) and ran diagnostics, but said everything was perfect with the Mac and the battery.


This worries me a lot because I don't use it a lot. I turn it on during the mornings for less than an hour, then turn it on at night for a few hours (4 hours tops). I sometimes leave it in standby mode, or forget and stays in standby mode for a few days without turning it off.

I don't use the Mac for anything heavy. Literally only web browsing and YouTube.


Why is the battery degrading so fast? This is my 4th Mac and never had issues before, and all my other Macs have lasted more than 5 years without any issues whatsoever.

 

[FreakinEurekan]

Is the battery working okay for your purposes?

If yes, problem solved.
If no, replace the battery.

Obsessing over the “battery health” without regard to battery performance is useless.

 

[chabig]

^^^ Very true. And also, the OP said he's using the machine daily. Of course the battery will slowly deplete. Even if he didn't use the machine, it would still deplete slowly because there are certain low power parts of the machine that operate periodically, even while sleeping.

 

[Mike Boreham]

I noticed something that has me worried. I checked the battery health like a month ago and it was at 94%. I purchased this Mac on October 2022.

However, I checked it again after a few days and it was at 90%

I've been checking the battery health regularly and it keeps dropping. Today it is at 87%.

I called Apple support (or authorized service centre) and ran diagnostics, but said everything was perfect with the Mac and the battery.


This worries me a lot because I don't use it a lot. I turn it on during the mornings for less than an hour, then turn it on at night for a few hours (4 hours tops). I sometimes leave it in standby mode, or forget and stays in standby mode for a few days without turning it off.

I don't use the Mac for anything heavy. Literally only web browsing and YouTube.


Why is the battery degrading so fast? This is my 4th Mac and never had issues before, and all my other Macs have lasted more than 5 years without any issues whatsoever.

Is this the Apple Health number or from a third party app like Coconut? There are not the same. The third parties use the ioreg number extractable with Terminal, and Apple is some unknown algorithm. I think the reason Apple does this is that the ioreg number can and does go up as well as down on a daily basis And they dont want people claiming new batteries as soon as it dips below 80%. I monitored my ioreg number for several months a while back and saw the chart below (reported here). Note in one four week period it went from 100% to 94%.

What is your Max Capacity in Apple Battery Health? Mine was 100% throughout the period in the chart, but I was using AlDente, to limit max charge.

 

[bradman83]

As others have said focus less on the battery health estimate and more on how well it actually performs.

My Apple Watch is four years old and the battery health is down to 83%, but I don't really notice a significant impact to how long the battery holds out. Were it not for me checking the health in the Settings app I doubt I would have noticed. Same for my iPhone 13 Pro, which lasts about as long as it did when I first got it for the same usage styles, despite the battery health being listed as 87%.

If longevity does become an issue then look into having the battery swapped out at an authorized repair center, but I doubt you'll notice a huge difference until you're ready to consider upgrading your machine anyway.

 

[ignatius345]

Also, battery health estimates are just that: estimates. Tracking individual percentage points of change is just going to be confusing. Looking at Coconutbattery, my own MacBook Air shows a sort of sawtooth pattern trending downward. Sometimes it's higher than a previous reading, but over time it averages out to a general downward curve.

As others have said, just use your battery as you see fit and then have it replaced when it's no longer holding enough charge to meet your needs.

 

[Ruggy]

I've said this before but it's still true. I inherited my phone 4 years ago from my wife and it was at 84% then and is still at 84% today.
I don't take a lot of notice of what battery percentages say on the phone or the mac as they can seem to jump quickly and then do nothing for years.
A piece of advice though: try not to let it drain to zero before you recharge it. That seems to degrade them quicker than anything else.

 

[Miles Fu]

you can limit the charge to 80% of the battery capacity by some apps, this will extend the battery life if your notebook is mostly plugged with charger.

my battery still has 88% health after 4.7 years. I also installed the app for another M1 Pro MBP, works pretty well too.