Thanks in large part to more efficient processors, the battery life of Apple's MacBooks improve with each new model year. That all-day battery life of a new MacBook will slowly begin to fade, however, and have you scurrying to a wall outlet with greater frequency as it ages. (Hey, none of us stay young forever.) You'll find a few settings in the Energy Saver panel in System Preferences for dimming and turning off the display, but there are other things you can do to help extend the running time of your , or .
Show battery percentage
Keeping an eye on the remaining battery life won't make it last any longer, but it can help you plot out how much work you can get done before you need to recharge. If your MacBook shows only the battery icon in the menu bar, I suggest adding the percentage next to it. Just click the battery icon in the menu bar and click Show Percentage.
Check battery condition
The next thing you will want to do is check the condition of your battery. To do this, hold the Option key on the keyboard and click on the battery icon at the top of the menu bar. You'll see one of four conditions:
- Normal: The battery is functioning normally.
- Replace Soon: The battery is functioning normally but holds less charge than it did when it was new.
- Replace Now: The battery is functioning normally but holds significantly less charge than it did when it was new. You can continue to use the battery until you replace it without harming your computer.
- Service Battery: The battery isn't functioning normally, and you may or may not notice a change in its behavior or the amount of charge it holds. Take your computer in for service. You can continue to use your battery before it's checked without harming your computer.
According to Apple, a MacBook battery is designed to retain up to 80 percent of its original capacity at 1,000 complete charge cycles. To check your MacBook's current count, hold down the Option key and click the Apple icon in the upper-left corner and then choose System Report. Next, click Power from the left panel and look for the number for Cycle Count under Health Information.
Dim the display
Powering the display is the biggest drain on battery resources. So, first things first: Lower the brightness of your display to a level that's comfortable for your eyes. The brighter your display, the shorter your battery life. You can also set the display to dim slightly on battery power and to shut off after a period of inactivity by going to System Preferences > Energy Saver. And if you work on battery power in a bright environment, you might want to disable the auto brightness feature. To do so, go to System Preferences > Display and uncheck the box for Automatically adjust brightness.
Keep current with software updates
Staying current with MacOS updates will help you get the best possible battery life. To check to see if an update is available for your MacBook, go to System Preferences > Software Update. While you're here, you can check the box to Automatically keep my Mac up to date, and clicking the Advanced button will let you check for updates automatically, download them automatically or install them automatically.
Kill keyboard backlights when not needed
A backlit keyboard is great for typing in the dark, but it can also drain your battery. You can set the keyboard backlights to turn off after a period of inactivity so that they're on when you need them and off when you step away. Go to System Preferences > Keyboard. On the Keyboard tab, check the box for Turn keyboard backlight off after ____ of inactivity. Your options range from 5 seconds to 5 minutes.
Turn off Bluetooth
There is a good chance you won't be carrying around a Bluetooth mouse or speaker when you leave your desk. With nothing to connect to, there is no point having Bluetooth enabled. I recommend disabling the radio to conserve battery. Just click the Bluetooth icon in the menu bar and choose Turn Bluetooth Off. Or you can go to System Preferences > Bluetooth and click the Turn Bluetooth Off button.
Quit applications you are no longer using
It's best to close programs when you are done using them. This can be done by clicking the Command and Q keys at the same time, or clicking on the program in the top menu bar and selecting the Quit option. To see how much energy each of your open applications is using, open the Activity Monitor and click the Energy tab.
Disconnect unused dongles
As with Bluetooth, if you aren't actively using a USB-connected device (such as a flash drive), you should unplug it to prevent battery drain. If the power cord isn't connected, charging your smartphone or tablet via the MacBook's USB port will also drain your battery.
First published Aug. 27, 2014.
Update, Dec. 6, 2018: Adds information about MacOS Mojave.