How to keep the juice flowing

If you are using the laptop as your primary computer and keeping it plugged into the electrical outlet all the time, removing the batttery is fine.
Many companies actually recommend against keeping the battery constantly plugged in,as heat and other factors could affect its internal chemistry and shorten its overall life span.
Sudden surges of current from the wall outlet can do bad things to computer,modems and other delicate electrical equipment.
To help protect against electrical fluctuations,many people use a surge suppressor - a device that goes between a computer's power cord and the wall outlet.
If you want to make sure your computer has a backup power system in case the electricity fails,you might want to buy an uninterruptible power supply.
Beside protecting your computer from electrical fluctuations.a UPS can also serve as an emergency battery backup when the power goes out,to give you enough time - two to five minutes - to shut down the compputer properly.
A detailed explanation is at http://computer.howstuffworks.com/question28.htm
If you don't use the laptop battery,charge it to about 40% to 50% of its capacity and tuck it away in a cool, dry place.