The quantity of Li in the crust is directly relevant. It provides an overwhelmingly more meaningful measure than "reserves", which only identify how much is in

The quantity of Li in the crust is directly relevant. It provides an overwhelmingly more meaningful measure than "reserves", which only identify how much is in the next place people will dig when their current seam is tapped out. What the number shows is that there is no possibility of ever tapping out all available lithium, no matter how many batteries are manufactured. Once the world is saturated, used-up batteries will become the main source for materials to build new batteries from. The more immediate limitation is rate of manufacture of batteries, because building battery factories takes a long time.