" there are many old EV's in China.."But not so many have...

" there are many old EV's in China.."

But not so many have expired batteries. I saw a talk by BYD's VP last year where he showed some numbers. There are a lot of BYD cars that are now beyond 500,000 km and the worst degradation performance still means the batteries still have 85%... and that is the worst. There are many beyond 500,000 km that still have upwards of 92-94% range.

You'll find that the feedstock for the recyclers comes from 2 other sources.
A) Other devices like phones
B) Off spec manufacture - batteries that fail QCQA, thought to be in the range of 10-15%

The wave of old spent EV batteries hasn't even started to form, let alone begun to break.