I'm no stranger to the PX13, as it was quite common in 60s and 70s SLRs-I have a lot of Canons that use it, along with my Nikkormat and my grandfather's Konica. I've always used a type 625 Zinc-Air hearing aide battery. These give the correct voltage(1.35V) and are stable over their lifetime(like Hg batteries), although the downside is that they only last a couple of months. They are cheap, though-about $10 for 8 and last ages in storage. I'm working out of a stash that I bought in 2008 or so, and they will come right up to 1.35V within a few minutes of pulling the plastic tab. There's a commercial product called the Wein cell that is a 625 in a metal ring to replicate the size and shape, but I usually just let a 625 rattle around in the chamber. For two battery systems(like the Photomic or the booster for my FT/Pellix), I generally wrap two in scotch tape and then poke some hols in the joint to allow air circulation.
Bookmarks