Material World: The Six Raw Materials That Shape Modern Civilization

by Ed Conway

Before a cell has been allowed anywhere near here it needs to be pulled apart from the rest of its battery pack, something that is far easier said than done. Battery manufacturers tend to prioritise passenger safety over everything else, with the upshot that the packs being put together at Gigafactory Nevada are so tightly closed with adhesives and fasteners that there is no easy way to disassemble them. So one of the hardest steps in the recycling process is actually the first one, pulling the battery pack apart, ideally without setting it on fire. The next step, however, is precisely that. Those little batteries are dropped into an enormous blast furnace where they are smelted down into a molten liquid. If you think this sounds a lot like iron manufacture, you’re not entirely wrong, except here the molten liquid coming out of the furnace contains nickel, cobalt and copper while the slag being drained away contains the lithium. Watching the batteries tumble into the top of the furnace is an unexpectedly satisfying experience, because after each one drops into the steaming mouth there is a sort of belch of yellow sparks and steam as it is digested. This belch, it turns out, is the energy stored up in that lithium, helping fire the furnace and melt the rest of the contents. As you watch the smelting and then the treating of these metals, what’s striking is how similar it all is to conventional mining. Umicore simply does with the lithium slag that comes out of its furnace m...