Shut down the computer, but plug it in to a power source while off.
Insert the battery again, connect the laptop to a power source and turn it back on.
If you have a newer Mac Book model without a removable battery, the procedure is a bit different.
A couple of different symptoms can come along with having a battery percentage meter on your Mac that is inaccurate.
The most obvious one is your computer randomly shutting off and dying before the battery percentage hits zero percent or even gets low.
In the support document, Apple addresses the issue and assures i Phone 6s and i Phone 6s Plus users that it is working on a fix.
Weirdly, the company says the issue is caused by time zone changes, whether done manually or automatically while traveling (via Mac Rumors).
The geniuses behind the Genius Bar at your local Apple retail store are probably capable of fixing the battery accuracy issue pretty quickly.
Chances are they’ll take care of it using one of two methods depending on the cause. This is covered if you’re under warranty, including the one-year limited warranty if it’s a manufacturer’s defect. Coming in at 9 are the replacement batteries for any Mac Book Air, the 13-inch Mac Book and the 13-inch and 15-inch non-retina Mac Book Pros.
Unplug the Mac and start using it, letting the battery drain naturally.
Eventually the battery will get low, so let it drain until the computer automatically goes to sleep.
Otherwise, a Genius Bar appointment at your local Apple store might be necessary.i Phone users, listen up: We have written a detailed guide on charging your i Phone properly. The System Management Controller, or SMC, on your Mac is buried within the operating system and groups together various functions involving the display, battery power, booting, shutting down, sleeping, and more.