R-CR-V3 Battery mystery

Took a couple of fully charged CR-V3 rechargeables on a foreign trip to
test with my Oly D-560. At home, after full charge, I can get hundreds
of photos. I left them out of the camera for four or five days,
preferring to use NiMh's, for which I brought a tiny charger. I could
get an almost full day's shooting with two, including heavy lcd use for
both taking and reviewing photos.

Ok, when I put one of the CR-V3s in I could only get about 25-30 shots
before it poooped. Ditto for the second battery. Came home and
recharged. Put one in my camera and so far it has gone four days and
60-80 photos with lcd and download to computer without any hint of power
failure.

What could be going on here? The out-of-camera dischange rate is
supposed to be pretty low. Could my camera simply require very high
voltage? But even it this is the case what could account for the HUGE
differences in performance between a battery that has been out of camera
unused for a few days and one that is in the camera freshly charged?
Why hundreds of photos in one case, 35-40 in another? Could voltage
drainage in the battery be less when it is in-camera than out?

Any thoughts, especially from experience, appreciated. Thanks.