Re: Battery life when plugged in
If it is a lithium-ion battery then no, you cannot prolongue the battery life by doing that. Lithium ION batteries do not have the memory effect found in older model batteries. The downside is they have less of a life span.
Generally speaking lithium ion batteries will only last about 1.5 to 2 years and still give you a full charge. This will happen whether you keep it plugged in or unplug it when not charging.
Long story short - no. it will not help your battery life by keeping it unplugged when not charging.