older Nickel-Cadmium battery-chargers are not safe to use with Nickel-Metal-Hydride-batteries.
There are newer-battery-chargers which charge several-different-rechargeable-battery-types,
usually including Ni-Cad & Ni-MH battery types;
Some require manual-battery-type-selection, some have automatic-battery-type-selection.
Each kind of rechargeable-battery requires different charging conditions,
many battery-types can explode or rupture if improperly charged
(like charging with the wrong charger/parameters).