I looked into it a bit and didn't get any satisfactory answers. From what I can tell , lithium comes from digging big holes in the ground and it's quite a toxic process to extract it. As for the batteries - at this stage their lifespan is limited and they are non recyclable and have to be carefully disposed of because of toxicity.
I am also somewhat concerned about the so called 'giga-factories' being built by Tesla to meet the demands for their products.
Saying all that, I'm still fairly optimistic about the future of clean energy.