We have accumulated a large amount of old car batteries. They are in all sizes. From small that weight around 6-7 kg to large ones that are 60-70 kg heavy. We have already poured the acid from them. Now as they contain a lot of lead in them we would like to extract it. What would be the best method to do that? I was thinking of cutting the top off with an angle grinder, remove the top with all of the plates attached and then remove one by one with a saw (not with an angle grinder because it would spread lead dust all over the place). Also as there is PbO2 in there also what would be the best method from keeping it from flying all over the place while removing the lead plates?