"Smart Battery System (SBS) is a specification for determining accurate battery capacity readings. It allows operating systems to perform power management operations based on remaining estimated run times. Through this communication, the system also controls the amount the battery is charged. Communication is carried over an SMBus two-wire communication bus. The specification originated with the Duracell and Intel companies in 1994, but was later adapted by several battery and semiconductor makers." From Wikipedia, 4/9/2012 http://en.wikipedia.org/wiki/Smart_Battery