Fun fact about li ion batteries: The lithium content of an 18650 cell is just under 2% by mass. The lithium content of (evaporated) brine is higher than that!

Fun fact about li ion batteries: The lithium content of an 18650 cell is just under 2% by mass. The lithium content of (evaporated) brine is higher than that! Even the lithium content of rocky lithium ore (spodumene) is around 1.35%. Right now extracting lithium from batteries is more difficult than mining it in the first place! It's just way too easy to extract, so lithium accounts for less than 1% of the price (haven't checked that lately, but it's been true even through large price surges). Hell, the total material inputs for an li-ion battery are something like $20/kWh including electricity and fuel. The price almost totally comes down to the scale and efficiency of manufacturing. Hopefully this changes but right now the lithium containing fraction of recycled cells is just used as filler material- concrete aggregate etc. Gravel, basically. Crazy.