Be careful about overcharging your battery though. I killed my laptop battery by keeping the battery attached to the laptop and the laptop was plugged into the outlet 24/7 for something like 9 month whether I was using the laptop or not.
That caused my battery life to drop from it's typical 5 hours to less than 10 minutes on a full charge. After several months of fully charging and full discharging the battery I managed to get it back up to about 2.5 hours on a full charge, or 50% of it's original capacity.