Battery charger recommendations

[Geneva]

One of the battery chargers made a clicking sound so we probably need to replace it. I'm going to replace both just to be safe. Appreciate any advice.
On edit
The charger makes the sound just before the light goes from red to green, more of a few clicks. Its not hot and doesn't smell. I had it charging the battery to see if i could get it to replicate the sound and it did, DW heard it when I was outside.
Thanks

 

[Jeremy McCreary]

If possible, safest to replace with the bike manufacturer's charger for your battery. That way you know they're compatible from a battery management system (BMS) standpoint.

 

[PedalUma]

It is really odd output for a charger. Like a tire pump it needs slightly more output than the final pressure or in this case voltage. A 36V battery takes a 42V output charger. A 48V output charger is weird. Unless it is really a 54.6V output for a 48V battery. The clicking sound may be perfectly normal for a safety switch. Plug the charger into the battery first, then into the wall. It should be fine. What does the sticker on the back of the battery say? What does the input connecter from the charger look like compared to a dime or a calliper?