I’ve killed a couple with my grinder, I would be interested to know which clones you use.ive killed a few XR batteries just form using them in a grinder with a wire brush...they just drain to the point of no return after a few quick cycles...brilliant in the drill and impact mind you, but gotta be careful with the grinders...ive moved to clones now, they seem to have a bit more poke...interesting to see how long that welder would last on a charge though