Prolonging battery life

[fuligin]

I have noticed that my battery level keeps decreasing by 1 digit from time to time. Additionally I hardly use my battery for portable computing as my laptop is virtually allways pluged in.What is the best way to prolong the batteries ovarall lifespan. I currently have it set to start charging when below 90% and stop charging when it reaches 99%, this has cut back my cycles, however im not actually sure if it does any difference.
Would i be able to just get rid of the battery all together, I have an APC surge protector if that helps for surge problems.

Thank you all in advance for your suggestions.

[Kaervak]

From what I've read, when you're not going to be using the battery for extended periods of time it's best to store it at 40% charge in a cool dry place. I have an Inspiron 8200 that's been on AC for almost all it's life. The laptop/battery is four years old and the runtime on it is almost the same as when I got it. Cycles alone aren't the biggest factor in battery life.

[jdhurst]

First, a surge protector will not help you if you have no battery. You need a good UPS.

Second, a battery is chemistry, and it starts getting "used" as soon as you use it once, whether you use it again or not. It will inexorably decrease over time. My TP is 32 months old. It is on the original battery, and if I was truly honest with the loose nut behind the keyboard, it would have been replaced at 24 months. It is still good for an hour and a half and serves me well enough, but it is past prime by months. Use it, forget about, and replace it whenever necessary.

... JD Hurst