Here's what was happening with the battery box I got from Sound Professionals, which uses this battery (click on the pic):
http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?item=SP-MINI-9V&type=store&category=310I was using it with a rubber band, but the battery would continuously become dislodged in the box - I was able to open it when I had a rubber band around it, and fix it, but the entire time I was worried about the battery becoming dislodged, and thus not power the mics, which meant I had to hold it perfectly steady.
I attributed this repeated battery dislodging to the fact that I had a rubber band holding it, and not having it screwed closed - there is a peice of foam on the bottom of the holder, and I though, for some reason that the foam was not holding the battery in the correct spot. SO I put the screw back in.
THen the battery became dislodged in there, even when I had it screwed in. NEeded a screwdriver, didn't have one...
My opinion is that if the battery is in there, and it is assembled as Sound Professionals desires, and the battery keeps popping out of place, it's a peice of trash. I have lost many recordings with my particular battery box b/c of this, rubberbanded or screwed.
My advice, based on my personal experience, is to get one that doesn't screw closed, and doesnt need a rubber band instead; I would also advise to get one that uses a standard 9v battery that has a little wire going to the battery (like almost everything else) so if the battery moves in the box a little, you still have a connection...
HTH-
Pfife