By replacing a single defective cell in a Battery, you can repair a Hybrid Vehicle battery, so I'm presuming it might be the same for full EV vehicle batteries. It must be noted that it is often cheaper to replace than find, replace and test, warrant the repair.That was in 2021 & it's increasing over time.
The fact is they are 90% recyclable - why such small numbers are being sent for recycling is a question for EV owners + manufacturers/repairers.
There is also some promising results at the moment with re-use & re-purposing the batteries.
Won't be something I'll need to worry about in the short term though.