Introduction

If there’s one area where you can read all sorts of contradictory information, it’s about the best way to keep your battery performing as well as possible. This is especially true for Intel CPU laptops where you might get unrealistic figures and sometimes problems.

A technical note published by Apple on this subject provides the calibration procedure (http://docs.info.apple.com/article.html?path=Mac/10.5/fr/9036.html). Here’s what it contains:

Calibrating the Battery

  • Connect the MagSafe power adapter and fully charge your MacBook or MacBook Pro battery until the light on the power adapter turns green and the battery icon in the menu bar indicates a full charge.

  • Leave the battery in a fully charged state for at least two hours. You can use your computer during this time as long as the adapter remains connected.

  • Disconnect the power adapter while keeping the computer turned on and start using it with the battery as a power source. When the battery is getting low, you will see a warning dialog on the screen.

  • Keep using your computer until right before it goes to sleep due to low battery. Save your work and close all applications just before the battery drains to the point where the computer goes to sleep.

  • Turn off the computer or allow it to go to sleep for at least five hours.

  • Connect the power adapter and leave it connected until the battery is fully charged again. You can use your computer during this time.

Repeat the calibration process approximately once every two months to maintain optimal battery performance. If you use your MacBook or MacBook Pro irregularly, it’s better to recalibrate the battery at least once a month.

You can check the charging capacity of your battery with many software utilities, or simply in the power section of System Information. Sometimes, after a complete calibration, you’ll see the capacity of your battery significantly reduced. It’s not this process that damages it, but regular use. Calibration only tests the battery over a complete cycle to prevent giving you incorrect usage times.

Edit this page

Last updated 22 Apr 2008, 06:13 CEST. history