Tesla's battery packs are really just a very large array of relatively standard lithium ion cells, 18650 lithium ions if you're curious. These individual cells

Tesla's battery packs are really just a very large array of relatively standard lithium ion cells, 18650 lithium ions if you're curious. These individual cells fail independently of each other, so the packs slowly degrades over time as a bell curve function of the MTBF, a Tesla battery can be "rebuilt" at any point in time during this lifecycle by replacing the individual dead cells within it. These individual cells that have gone bad over time and no longer hold a charge can be "recycled" more completely, where the individual materials and electrolytes are separated, processed and reconstituted as a new battery that can then be used in a pack rebuild or a new Tesla car or wall pack.