How Do I Replace The Apple Remote Battery?
The Apple Remote uses CR2032 or BR2032 lithium coin batteries. This is a very common type of battery, so you can buy replacements at just about any store that sells batteries.
For a second generation Apple Remote, use a coin to open the battery door on the back of the remote. Swap the old battery out in favor of the new battery, then close the battery door.
The first generation Apple Remote battery replacement is slightly different. Press a paper clip or pencil against the bottom of the remote to release the battery tray, then replace the old battery with a new one.