How do you remove rusted battery hold down?

To remove a rusted battery hold down, start by applying a penetrating oil, like WD-40, to the rusted areas and allow it to sit for several minutes. Use a socket wrench or pliers to attempt to loosen the bolts or clamps. If they remain stuck, you may need to use a wire brush to remove rust around the fasteners or a rust dissolver. In extreme cases, cutting the hold down with a Dremel tool or saw may be necessary.