Are we talking
about more or less standard gel cells? The 2V terminal voltage
would seem to indicate so.
Yes.
Those are *very* standardized, in terms of
similar sizes being offered by a
great many different manufacturers. When I was doing the retail battery
thing some years back (roughly 1993-5), we carried PowerSonic and one other
brand I'm not remembering at the moment, and the sizes for similar
capacities was a pretty good match for the Panasonic units listed in the
Digi-Key catalog. Folks would come in with all sorts of other units and I
was usually able to match them up with something that would fit.
I'm not concerned about specific vendors - just D-sized (to fit the
enclosure) with solder-tabs.
If they're cylindrical (and if the 'D size' means the same size a a
D-size primary cell (like a torch (flashlight) cell), then these sound
like 'Cyclon cells'. The smallest one of those is about the same size as
a D-cell and it's 2V, 2.5Ah.
Last time I needed some (for HP9114 disk drives and 110/110+ computers),
I had no torouble in getting them in the UK.
-tony