replacing mackbook pro battery early2011

Whenever you encounter a screw that is stuck, you need to be very careful not to destroy the head of the screw or you compound the problem. The first thing I would do is open the lid of the laptop and place the laptop upside down on a flat sturdy table top (the keyboard/palmrest is upside down on the table) with the open display hanging down over the front edge of the table to protect it. Now you can lean into the screw driver with a bit more weight to help the driver to bite into the screw without risk to cracking the display with the extra pressure.

If you have rounded the screw head, then you are going to have problems. You can try a different size Tri-wing driver which may find a spot to bite into the screw just enough to loosen it. Since this is a Tri-wing screw there are probably not a lot of options. Normally I would try using different drivers to try to get a bite into the screw head such as a phillips driver, perhaps a torx driver, or even a flat blade, but I doubt any of these will do much for a Tri-wing. You may even damage these other drivers in the attempt.

I find the plastic mount of the battery for that left screw usually tends to become cracked or even broken. If this is so, then just finish breaking the plastic mount off the battery which may allow you enough room to remove the battery if enough of the plastic has broken off. Once the battery is removed, then you may be able to use small vise grips to grab the stuck screw to loosen it.

Please be patient and don't keep bumping your thread or creating multiple threads. This is a user to user volunteer forum. We are just other regular users such as yourself. Apple is not here. You are unlikely to get an instant response. Sometimes it may take a day before someone comes across your post who can even answer it. Please don't create multiple threads as it just causes confusion and wastes the time of the contributors.