Hi there. I have an early 2008 MBP (MacBookPro4,1) and have used it for a little over 4 years. The battery is starting to die on me whenever I use it portable so I've been using it as a desktop, plugging it in 100% of the time instead. The battery compartment looks normal, no bulges or anything. I just noticed I am getting a "Service Battery" alert in the battery drop down menu. I didn't buy Apple Care so I don't think they'll be giving me a free replacement. Should I even buy a new battery since I only use it at home? And if I keep plugging in like this, will the battery explode? I appreciate any help! Thanks!