Hello rnavagamuwa and welcome to Seven Forums.
You may get different opinions on this, but no. You shouldn't have any problems leaving the laptop plugged in to the AC power. Some people leave the AC adapter plugged in all the time when using the laptop at home. Others just remove the battery and run off of AC power. Still others (and this is what I do) will remove the AC adapter every so often and run on battery power only. When the low battery alert appears I plug the AC adapter back in and let the battery recharge.
Every modern battery has a limited number of charge/recharge cycles so eventually, every battery will lose its ability to hold a charge. This is usually a gradual process and you'll notice that instead of having 3 hours of battery time it's now 2 hours, and then 1 hour, etc.
Why do I leave the AC adapter plugged in? One primary reason. I live in an area that experiences frequent power outages. If the main power goes out I still have the laptop battery available so my laptop doesn't just shut down. The same thing could be accomplished with a backup Universal Power Supply. Notebook Battery Guide Basic to Advanced Battery Information from Battery University