Is there a reason why MacBooks stop charging at 99%?

How To Fix Your Macbook Battery That Won’t Fully Charge

A little over two weeks ago I purchased this new Macbook Air and so far I simply love it. It has incredible battery life and everything seems to perform beyond my expectations.

You can only imagine my concern when I noticed that the battery indicator on my Macbook Air was lit green and done charging but MacOS listed the charge at just 97%. Had I already lost 3% of the usability of my Macbook Air in just a couple weeks!?  Some of you may be wondering your Macbook won’t charge past 80%. 

Turns out that this was not a problem at all but a feature included in every Macbook. I know what you’re thinking and no it isn’t a feature like Antennagate and the iPhone 4. Apple purposely keeps your charge below 100% and apparently, they do this for a very good reason. It helps extend your battery life.

During my search to fix my macbook battery problem I also found out how to quickly restore my battery indicator to 100%. It turns out, all I needed to do was unplug my Macbook Air for a few hours and it would fix itself.

Apple explains this battery preservation feature on their site:

This is normal. The batteries used in these computers are designed to avoid short discharge/charge cycles in order to prolong the overall life of the battery.

When setting the Mac OS X battery status menu bar icon to display charge state by percentage, you may notice that the reported charge stays between 93 or 95 percent and 99 percent.

To allow the adapter to recharge the battery to 100%, simply allow the charge to drop below 93%. The adapter will automatically recharge the battery to 100%.

If you still think you have an issue with your battery, Apple provides instructions on how to check your battery health on their support page.  It may recommend that you service your battery if there actually is a problem. Contacting your local Apple store would be your next step.

Can Your PC Do That?

One thing I hear more often than not from individuals that switch from a PC to a Mac notebook is how amazed they are by the battery life on Apple computers. Maybe this is because of battery preservation features built into the software and hardware.

By prolonging the battery life through smart charging, Apple not only improves their user experience (albeit with a bit of user confusion about the state of their battery) they also outperform and outlast most of their competitors. 

If your Mac battery won’t charge completely

It’s normal for your Mac laptop to stop charging before 100% to optimize or extend the lifespan of the battery. These features may be why your Mac battery won’t charge completely:

• Optimized Battery Charging: If Optimized Battery Charging is enabled in Battery settings, the battery on your Mac laptop may delay charging past 80% in certain situations, even after the power adapter has been connected for an extended period of time. This behavior is normal and helps optimize the overall life of the battery. If you need to have your Mac fully charged sooner, click the battery icon  in the menu bar, then click Charge to Full Now.

  Note: If Optimized Battery Charging is turned off and your Mac still won’t charge past 80%, the battery temperature may be too hot. Move it to a cool, well-ventilated spot.

• Battery health management: Your computer may have temporarily paused charging to extend the lifespan of your battery. Your battery may drain to 93% or lower before it begins charging again. See the Apple Support article About battery health management in Mac laptops.