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.
If your Mac won’t charge at all, see If your Mac battery won’t charge.