This is because of expiring patents which create an artificial inflation of businesses' durable market value for the incumbent allowing them to monopolize the market via supply scarcity. Naturally there would have been more recycling the entire time if it were not restricted by patents.
Or, less conspiratorially, it's because the volume of batteries that need recycling has been steadily growing.
Sorry what?
Which patents were the biggest hold backs in the recycling industry? I am curious how the patent landscape looks today compared to a decade ago. Seems like it would be exploding in more recent history.