Despite early concerns that the MacBook Air battery is unaccessible to end users, Appleinsider claims that there are no special tools or knowledge required to swap out the MacBook Air's battery.
A standard size-0 type philips is all that's required to open the MacBook Air. The replacement process is described:
Given the history of iPod battery replacements, there was some concern that users would be unable to easily replace the MacBook Air battery. Apple has said that a $129 replacement will be available but will require the MacBook Air to be sent in from Apple. If the battery replacement is this easy, however, 3rd party batteries will certainly also be available.Once flipped upside down, the MacBook Air's bottom cover is easily unscrewed and removed, providing immediate access to the battery cavity. From there, the battery can be unscrewed from the chassis with the same screwdriver and unplugged from the circuit board with a simple tug -- it's not soldered to the board.
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