Quote Originally Posted by Gerald C Koch View Post
IIRC correctly the only difference between the Wein and a regular zinc-air hearing-aid battery is an additional hole to allow for more oxygen.

If your camera is not to be used for awhile remove the battery and cover the holes in it with a bit of black electrical tape to keep it fresh.
Wien cells have two holes, standard cells have four. You need only one for the intermittent and very light drain of a camera meter. I've got over two years on a cell with three of the four holes blocked. Two years last April, to be more precise.