Discussions

At first I thought maybe my laptop was try to bit the dust....  
 
The screen on my laptop looks like it is lickering....kind of like small surges. This only happens when I have the recharger plugged in. I had thought maybe there was a loose connection,but everything seems fine.  
 
When I unplug the charger....the screen is fine.  
 
So....could this be a battery issue? My laptop is about 4 yrs old now...and I have never repurchased a new battery. Is this a common thing to have to do. It doesn't look like its charging up either..not much power left for the amount of time its been on the charger.  
 
Does anyone have any ideas or can any tell me what the life time of a laptop battery is?