Used in lead-acid batteries for automobiles and backup power systems due to its ability to store and release electrical energy efficiently. Common in radiation shielding for medical and nuclear applications because of its high density and effectiveness in blocking X-rays and gamma rays. Employed in construction for roofing, flashing, and soundproofing materials. Historically used in paints, pipes, and gasoline, though many of these uses have been phased out due to toxicity concerns. Still found in some solder, weights, and ammunition.