Sibi Marcos asked about removing a laptop's battery to increase it's life.
Here's one of those sad facts of life that you just can't avoid: Like cars, clothing, and people, batteries wear out. You can't stop this process, but with proper care you can slow it down.
What wears down a battery? Charging and discharging. Obviously, you can't avoid either of those acts entirely (although if you could, you wouldn't have to worry about wearing out your battery). The trick, of course, is to do as little charging and discharging as possible. And one way to avoid charging and discharging is to remove the battery when you don't need it.