All batteries eventually wear out and lose the ability to hold a charge. You may need to replace your battery pack after a year of average usage.
All batteries lose their charge if they sit unused for an extended time period. When not used, battery can discharge fully in 2 to 3 months.
Increasing Battery Life
If you plan to use your notebook computer without the docking station, increase battery life using the following methods.
General Environment
Using the methods below you can increase battery life by as much as 1.5 times.
•Detach the docking station.
•Detach any unnecessary USB and PS/2 devices - (camera, mouse, keyboard etc.)
•Do not use any Multimedia programs - (Windows Media Player, audio/video CDs) unless absolutely necessary.
Adjust LCD Brightness
Reducing the LCD display brightness will reduce the power consumption of the battery. However, if you require the screen to be bright the computer will automatically reduce the brightness after 20 minutes of inactivity. The screen will be returned to original settings when you resume your activities.
To reduce the LCD display brightness use the 
+ 
key combination.
Power Management
To change the time until your computer goes into reduced power modes, use the system power management function.
1.Click Start > Settings > Control Panel.
2.
The power options panel enables you to reduce the time until your computer goes into standby mode for example. See “Using Power Management Options” on page 57 for instructions on how to use this battery saving tool.
Using the Battery 47