I thought a room batten would be a piece of construction material (i.e a wooden batten long enough to be the entire length of a room, to which plasterboard or other material could be fixed). Was actually considering doing this to soundproof my studio and workshop so I could turn up the music at night, but it would be a huge mission getting all the stuff delivered and measuring it up, plasterboard isn’t cheap and it would have to be filled in the cavity with other stuff, and also the place would become hotter than the Borneo jungle especially in summer..)