My question to all you electronic gurus on here is...How do you know when it's time to replace your battery charger?

I would assume it would quit charging the batteries, right?

The reason I ask, I took the boat out over the weekend and batteries seemed fine on Saturday. Sunday was a different story though, they seemed half charged even though the charger was showing a full charge.

The batteries are basically new batteries, bought last fall.

Is it time for a new charger? :-/ Thanks in advance y'all.

I guess I shouldn't have whizzed on it last year.