You will not get back 100 % of the raw material in any economically feasible process though.

If your process gets 90% of the lithium out of the battery, after 7 cycles more than half of the lithium is gone. Therefore Mining can’t stop even when the market doesn’t grow anymore.

Current BESS are rated to last 10-15 years. Battery makers are already moving to lithium-free sodium chemistries. It's hard to imagine what we'll be using at the end of seven full cycles (70-105 years from now.) Sodium? Tiny fusion reactors? Firewood and charcoal? Yes, we should care about this and try to leave our descendants with good solutions. No, we should not think about it so much that we leave our descendants with a devastatingly acidified ocean and uninhabitable equatorial regions in the process of worrying about it.

The process of battery manufacturing is always improving, getting more storage with less lithium. So when a battery is recycled, it will actually produce more battery than the original battery, even with lithium losses.

We don't know how long that process will go on, but in any case the amount of lithium needed will be a steady state, assuming constant need for batteries. But much more likely we will see ever increasing demand for batteries, just as we do for steel or copper or whatever minerals power our current economy.