Do you know what the No. 1 most recycled product is? It's not what you might think: It's car batteries. Almost all of the car battery is recyclable. Sixty percent of it is lead, which can be recycled and used for other metal products. The three pounds of plastic is also reclaimed and used in the manufacturing of new batteries. And the sulfuric acid inside is safely captured and recycled in new batteries. If you replace your battery at a dealer or auto shop, your battery is recycled. If you have any old car batteries at home, take them to any auto shop, and it'll recycle them free of charge for you.