Q: I lost my Bluetooth keyboard battery cover.

raemizzang, welcome to Apple Discussions.

You will need to contact the keyboard manufacturer. They should have a web page. In the meantime, use some tape to cover the opening.

 Cheers, Tom

Go to this page. http://www.apple.com/support/serviceassistant/overview.html

 Cheers, Tom

I can't find a way to buy a cover, but I was able to make a cover by taking a quarter inch bolt, a combination nut/lockwasher and black electrical tape. Invert the nut/lock washer so that the locking part is facing out, then screw the bolt in until you feel it push against the battery spring on the inside of the keyboard, then tape the bolt/nut tightly into the opening with electrical tape.

Next, go look where you lost the original cover!

Ok, with my kludge fix in place, I looked in my briefcase again, and found the Apple original battery cover. Hint don't take the batteries out, the cover needs the pressure of the spring at the other end, to stay locked in place.

My battery cover was wedged into a crevice. Once I had the keyboard working, it was MUCH easier to see.

The same thing happened to us in the office. My boss took one of the cabinet locks (from Knoll office furniture) which happens to be 1/4 inch, cut it between the 3rd or 4th rib of the lock with a hacksaw and vice grip, placed the batteries in and used duct tape to hold everything in place. The duct tape works better than the electrical tape because electrical tape tends to stretch. Good Luck, apple doesn't sell this piece as a replacement so get creative!