Hobbyking is currently selling NiZn.
Someone has suggested a test of those, in the request thread for batteries:
I wonder if the problem with NiZn dying is due to over-discharge, over-charge, or both?
Could they be modified by adding a protection circuit, if so?
I bought the PowerGenix charger and eight AA cells, quite a few years ago (the original PowerGenix, not from HobbyKing)
I’m now down to four viable cells, the others died fairly quickly.
One of those four is noticeably overheating when all four are charged together, typical pattern.
The charger has “0911” pressed into the case below the label, and the label says “PG-ART-003-03”
and will handle “1 to 4 AA or 1 to 2 AAA” — four slots for AA, and the middle two slots also have contacts for AAA, so that’s a physical limit at least.
I don’t know if HobbyKing’s selling the same thing or a copy.