All batteries eventually need to be replaced. If your MacBook battery light doesn't tell you that you need to replace the battery right away, calibration can help you get the most out of your battery.

  Using your Macbook on the go requires keeping your computer on for as long as possible.So make sure your batteries are charged as much as possible to ensure your work can continue uninterrupted without an external power source.

  MacBook batteries require a calibration process to restore the internal lithium-ion battery and fully charge the computer.

1.Click the battery icon in the upper right corner of the screen.

During normal operation, the battery should show a "Normal" state.

If the battery states "Replace Soon," "Replace Now" or "Service Battery," then take the battery in to the local Apple Store for replacement or repair.

2.Plug the power adapter into your MacBook and charge the computer until the green light on the power cord turns green, or the power light on the taskbar shows the battery is at 100%.

3.After charging is complete, leave your MacBook plugged in and run for two hours.

4.Select the Apple icon in the upper left corner of the screen.

Click  "System Preferences" then "Energy Saver" .Set the "Sleep" slider to indicate "Never" under the sleep setting.

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5.Disconnect the power adapter from the MacBook. Let the computer run completely and shut itself down.

During this time, you can use your MacBook. Close all apps before the battery runs out to ensure you don't lose any data.

6.After the battery runs out, press and hold the "Power" button for 10 seconds to shut down your MacBook.

Leave it off for at least five hours.

7.Reconnect the charger to the MacBook and start the computer.

Keep the computer charged until the green light turns on, or the battery light shows that the battery charge is 100%.

If you want to know more about macbook, please go to:

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Meanwhile, batterymall.com provides high quality macbook batteries.