The battery life of the brand new MacBook Air is an enviable 12 hours (or more, as some reviewers found). If you can’t afford to run out and buy a new one, don’t worry: there are still things you can try to help preserve and extend the life of your older MacBook’s battery.
Whether you’re traveling, at an off-site meeting, are not able to get the one table at your favorite coffeeshop next to the power outlet, or just cannot charge your MacBook for an extended period of time, you should know these secrets of power-saving.
Check the condition of your battery. Before you attempt to maximize the health of your battery, you first need to determine if your battery is healthy or not. The easiest way to do that is to hold down the option key as you click on the battery status icon to access the Battery menu bar extra. You want to see a condition of Normal. If you instead see a condition of “Replace Soon” you may need to bring your Mac in for service and likely get the battery replaced.
Determine your battery’s cycle count. You find this by clicking first on the About this Mac menu in the Apple menu. Then click on the More Information button then the System Information button. In the left column, select Power from the list and locate Cycle Count. You can typically expect to get about 500 to 1,000 cycles out of your battery before it loses up to 80 percent of its original capacity, depending on the model year of your Mac.
Use a better battery monitoring utility. There are utilities that make gathering information about your battery’s health much easier. One is Battery Health (Free, Mac), which will tell you the original maximum capacity possible for your MacBook’s battery, which you can compare that to the maximum capacity the battery is currently reaching. An alternative utility is coconutBattery (donation, Mac). coconutBattery has the same information, but will also upload your battery’s statistics to its online service for comparison to other batteries in use by Macs similar to yours.
Calibrate your battery. Calibrating your battery basically maximizes its full charge potential by first fully charging it, then fully draining it, and finally fully charging it again. Apple does not recommend leaving your MacBook plugged in all the time. Furthermore, Apple even recommends charging and discharging your MacBook’s battery at least once per month — it even has a calendar event to remind you.
Restore Energy Saver defaults. The first step you need to take to ensure that you are getting the most out of your battery as possible is to restore your Energy Saver setting to their default values. Open up the System Preferences and select Energy Saver. Make sure that the Battery settings are exposed and click on Restore Defaults. This should turn the Mac off after 10 minutes of no use, the display off after two minutes, allow the hard disk to sleep when possible, and slightly dim the display when on battery power. Do not enable power nap, as that will consume power even when you think your Mac is sleeping.