Yeah, these are 0.5C cells, meaning they can safely discharge 157A (I would be using them for offgrid solar), so those little nickle strips would melt. I think TiG welding these would be extremely dangerous and produce too much heat (and I’ve never TiG welded before; just badly MiG welded a couple times). By “welding” in the description they mean commercial laser welders.

I don’t think those would work for these large batteries. I have one that I use for small cells though (i.e. 18650/21700).