Should I remove my laptop battery when using the AC adapter?
When you use a laptop computer close to a power outlet, plugging in the AC adapter to power the laptop is a good practice. Your laptop battery takes advantage of the power outlet and saves the battery for situations when there is no power outlet available. While using the AC adapter to power the laptop, you can leave the battery connected to the laptop.
Benefits of keeping battery in a laptop
There is no need to remove the battery and keeping it in has benefits.
First, if the battery is not fully charged, leaving it connected to AC adapter allows the battery to be charged to full capacity over time.
Second, having a battery backup is great for power outages and brownouts. If either occurred, you would not lose any of your data because your laptop switches to the battery backup.
Finally, even when fully charged, leaving the battery connected while using the AC adapter will not damage the battery. Over time, all batteries will eventually lose their abilities to power a laptop and need to be replaced. That's normal for a battery and not a side effect of using the AC adapter with the battery connected.
When should the laptop battery be removed?
Removing the battery from a laptop is only necessary if you need to do a hard reset or when replacing internal hardware. Other than that, the battery should always stay inside the laptop.
Like all battery-powered devices, if you plan on not using the laptop for over a year, it is a good idea to remove the battery. Store it in a plastic bag, or ideally an anti-static bag.