I know of someone who trashed a set of 20 Saft STM5-180 GC2 NiCd modules by overcharging them. He fired up his "bad boy" unregulated charger and forgot abouit it. By the time he remembered, some of the cell caps had literally melted.
Well, I torched 29 BB600's that way: The tops didn't melt but the cells shorted and burned holes in the sides of the cells. That was a combination of a reduction in cells plus a different capacitor to raise the final voltage plus a broken charge timer. Bad idea, bad me.
And I still recommend a charger with more smarts than that old GE blunderbuss.
Yeah. Oddly enough I have it plugged into a smart outlet and have been testing automations with Home Assistant to watch the current draw and shut it down when it reaches the trickle charge. I'm also programming in some smarts to detect if current starts to *increase* after bottoming out on a charge, that's the fingerprint of a thermal runaway about to happen.
Home Assistant is a TON of fun. All sorts of things you can do with it. Hilarious to use it on a 50 year old tractor, but there we are....
C