I'd say 30 years makes them VERY old. That refers to the sub-C's in the Gardner-Denver wire-wrap tool, but not those AA's in the much newer Uniden telephone. Those have about a 45-minute capacity, despite the fact it takes 18 hours to charge them, and that operating capacity decreases considerably with each charge cycle. After about a dozen cycles, they're useless, i.e. won't supply enough power to operate the phone for even a minute. When I put 'em in that current-pulse charger, it refreshes them, but the life cycle is as before and I have to repeat that process every few days.

Te seem to have the same capacity, i.e. 8 hours of pretty consistent usage or three weeks occasional use that they had when new. They don't seem to lose much charge when stored a long time. I had several sets fully charged and lying in the drawer for at least two years, yet was able to use them without recharging, which was a good thing, since I'd mislaid the charger. (I did find it, though, after a protracted easter-egg hunt.)

I suspect there's some sort of synergy between charger and battery in this particular case, though, as I've already said, I suspect I would be happy with the sort of longevity I get from the NiCd's in my electric razor.

RE