I know the lithium batteries are supposed to be a pain to recycle but how are the conventional ones broken down to recover all the materials?
I have a bucket I throw dead batteries into and picking it up made me realize just how heavy it is. That is a lot of metal. And metal is money.
The simplified answer is, they get shredded, then various processes both physical and chemical are taken to extract the important materials and the rest is disposed of. Often certain metals will dissolve in specific acids or chemicals, then you can take that liquid with the specifically dissolved metal and precipitate it out. Often melting it down can also separate different metals when they have different melting points.