Apple has acknowledged that some MacBook Pro batteries sold from February 2006 through May 2006 under perform, and has launched a worldwide battery exchange program. "We recently discovered that some 15-inch MacBook Pro batteries supplied to Apple do not meet our high standards for battery performance," Apple wrote. "To give our users the best experience possible, we will replace these batteries for customers free of charge." Apple says that the affected batteries do not pose a safety risk. Affected batteries display the model number 'A1175,' along with a 12-digit serial number that ends with 'U7SA,' 'U7SB' or 'U7SC.' Model and serial numbers are located on the bottom of the battery, which are only visible when the battery is removed from the MacBook Pro.

The company has provided a Web-based form to handle the exchange process for those owners affected by the new recall, requiring the serial number of the 15-inch MacBook Pro, the battery serial number, and a destination address for the replacement battery.

"After serial number verification, a new battery will be shipped to you, free of charge. When you receive the replacement battery, please use the same shipping packaging and included prepaid shipping label to return the recalled battery to Apple."

"It is important that you return the affected battery to Apple so that the battery can be properly recycled. Thank you for your cooperation with this exchange program."

Previous recall

Apple in May acknowledged another issue with some early MacBook Pro batteries, and offered to cross-ship fresh replacements to customers experiencing those issues. The first recall pertained to MacBook Pro models with serial numbers up to 'W8608,' or those models which were produced during the first two weeks.

Symptoms of the previous recall included battery power level going from a full charge to 90 percent, then immediately off; the battery often either goes directly to one blinking LED, or fails to respond at all; and some may experience a sizeable loss of battery capacity.