Apple has initiated a worldwide battery exchange program for certain rechargeable batteries that were sold for use with 15-inch MacBook Pro computer systems from February 2006 through May 2006.
A technical support document reveals that Apple "recently discovered that some 15-inch MacBook Pro batteries supplied to Apple do not meet our high standards for battery performance. To give our users the best experience possible, we will replace these batteries for customers free of charge."
The company notes that the affected batteries aren't unsafe, saying users can continue to use their current battery "until a replacement arrives".
Affected batteries have model number A1175 and a 12-digit serial number that ends with U7SA, U7SB or U7SC. These numbers are located on the bottom of the battery, which means you need to remove the battery from the Mac before checking for them. The battery serial number is located above the barcode.
Only batteries within the noted serial number ranges need to be exchanged. No other MacBook Pro or MacBook batteries are part of this program.
More information is available on the Apple website.