Welder - so far I have not found a 24v charger for sale in a brick and mortar store so I cannot try the fit. However the Hitachi's etc charging slot is either too small (need 1"x2") or way too big. There are also different configs for the charging tabs. Mine are pos and neg tabs on right and left and third tab (ground?) at the rear. Some have the ground at the front.

Do not understand you comment about using the wires. If I clip a wire on the pos tab of the universal charger and then clip the wire on the pos tab of my battery - is that different from just making a direct connection battery to charger?

Do you have any idea about the elec scooter charger? If it is built to charge a lead/acid battery for the scooter, can I use it on a nickel battery?