Battery Update 1.4

http://support.apple.com/downloads/Battery_Update_1_4

MacBook (13-inch), MacBook (13-inch Mid 2007), MacBook (13-inch Late 2006), MacBook (13-inch Late 2007), MacBook (13-inch, Early 2008 ), MacBook (13-inch, Early 2009), MacBook (13-inch, Late 2008 )

Follow these steps to determine if your battery needs this update.

From the Apple () menu, choose About this Mac.
Click More Info to start the System Profiler.
Locate the Hardware section and select Power.
Batteries with this information in the Battery Information section need this update:
A device name "ASMB016" or "ASMB013" in the serial number
A Pack Lot Code is 0002
A battery firmware version of 0110

Note: If the Pack Lot Code is 0003, the update is not necessary or has already been applied.