2000 Grand jeep cherokee

car dies,then when husband tightens battery cable, starts right up, he did this last week and broke off a piece of the thing that holds onto the battery (don’t know the name) its where you would put a jumper cable since then won’t start and all the dials in the car seem to go nuts. It did start when it was jumped

I’m sure there is, but I didn’t see a question in there…