Rita Baker wants to preserve her laptop's battery. Should she remove it before running the computer on AC power?
Doing so is probably the best practice, but it's a hassle that most people, including me, don't want to bother with. My laptop spends most of its time plugged into AC power, with a fully-charged battery inside.
Heat from the running computer can shorten the battery's life. For that matter, the heat from the battery doesn't do the computer any good, either. And depending on how smart your laptop is about power issues, it may be draining and recharging the battery as it runs--which could further wear it out.
That's why the best possible practice is to work most of the time on AC power with the battery out. Then, a few hours before you plan to run the PC off the battery, shut down the laptop, unplug it, put in the battery, plug in the AC power, and let it charge for a few hours. But really, who's organized enough to do that?
So here's what I recommend: If your laptop is likely to remain plugged for the next week or more, shut it down, remove the battery, and stick to AC power. (You should never remove or insert the battery while the laptop is on, even in sleep or standby mode.) However, if you use it unplugged with any sort of frequency, keep the battery in.
There's something else to consider: If you live in an area with frequent power outages, the battery is also protecting you from sudden crashes caused by loss of power. In that situation, you may want to keep the battery in--or invest in an Uninterruptible Power Supply (UPS).
Note: This post was altered on November 9. I corrected a typo. My thanks to Michael Scott for bringing it to my attention.