Who is Apple's lithium supplier?

Could you please clarify who exactly supplies Apple with lithium, the crucial component in their batteries? It's a well-known fact that Apple's products heavily rely on batteries, and lithium is a key element in their manufacturing. Therefore, identifying the supplier of this crucial material would give us valuable insights into Apple's supply chain and their commitment to sustainability. Is there a specific company or multiple suppliers that Apple works with when it comes to sourcing lithium for their batteries?