Depending upon the model, a notebook battery usually lasts from 1 to 8 hours. However, with efficient battery usage, an hour or two of battery power can significantly be increased. You can save battery power by using the built-in battery saving modes and by following good notebook battery-saving practices.
Built-in battery-saving modes are Stand By and Hibernate. In the Stand By mode, open applications are stored in the RAM, the hard disks power down, the monitor switches off, but the processor goes on running. When you again perform some activity of the mouse or the