Over 10 years ago, the notebook designs changed so you can leave the battery in the laptop and run off the AC line without any impact on the battery's 18 to 24 month life.
To maximise the life of the battery, don't subject it to excessive temperatures. Below freezing is deadly to some Lithium batteries and too hot (about 80C) is bad too.
Hope this helps,
Bob
Hi. Please suggest (for Dell Inspiron 8600 notebook) if the notebook can be allowed to remain connected to power while the battery is fully charged. Does it have any adverse effect on the life of battery. Also suggest ways to maximise the life of the battery.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic