Not a stupid question, no I do not have a battery hold down, the box it sits on it almost rusted away and I will be building a box for it, but I have had the car some 2019 and this is the first time the battery has ever moved itself, I think the length of the battery cable was the culprit, it's a little taught. I will be replacing the battery shelf and the shirt cable I'm just only able to do so many parts at a time and I will have to by my cable by the foot this time bc I bought the longest advanced had in 2AWG battery cables