Price of lead is hanging around $1.30. I'm sure there's more than a couple of pounds of lead in each battery. Could be a way to make some money if you figure out how to recover the lead safely.
Never try to open an melt...lead has acid in it....gives off super toxic gas.
Utter nonsence. The lead Acid Batteries have a mild form of Sulfuric Acid in them. However, this is dissipated to almost nothing as the battery is worn out. You can easily break open those and there is no such thing as a toxic gas given off. The easiest method is to turn them upside down and allow the liquid to just pour out. Rinse the area with a garden hose since the even weak acid will actually clean the area. It is an acid but in reality weaker than what people can buy at a place like Home Depot, Menards, Ace Hardware, etc. for cleaning concrete. I've melted many such plates from the inside with a Butane Torch for the Lead.