Some notebooks has a software that can make the battery not charged when it is in use, like IBM, but many of pc do not have it. So you have to take the battery out when you power your pc via adapter, it will longer its life.
Very nice articles. Batteries should be fully charged and recharged when there is no power in the battery. But when you charge it with an adapter, you'd better not use your laptop, doing like this, you battery will last very long life.