The top of the line Batteries last typically for 5 thousand hours. If you use your battery to run that thing everyday all day it will be on for almost 9 thousand hours. so, if you only run it 12 hours a day or leave it sitting in the on position it would be almost 4 thousand hours. Now, that would be if your battery was the best battery ever, and always kept in excellent condition. The average battery, in the average lap top only lasts about 3 thousand hours.

Take heart, as technology progresses we are making longer lasting batteries, and using greener technology to make our laptops. Till then, we keep shelling out money to replace those puppies.