Only a single experience, but i had to provide electricity for my servodrive (not yet installed). Since mine is in a peninsula location, the wiring is running through the cabinets not the wall.

Perhaps you can piggyback through an existing circuit so that you do not have to cut up your walls too much.

I've install a lot of servos but don't know anything about a battery pack or that was even an option. They work of a transformer that has to be plugged into an electric outlet but that can be in a remote location then you run the single low voltage wire to the servo or several servos can run off a transformer. Call Blum customer service in NC 800-438-6788 they are very helpful.