Zebra molten salt battery? It says they are not toxic and recyclable. There are a ton of different battery chemistries to pick from in the link.
I'd take a deeper look into the mining of any battery. The elemental makeup may be non toxic, but how they are mined could be environmentally horrific.
Weird and Wonderful Batteries - Battery University
Unfortunately these tires have no useful life. Someone didn't need them and didn't want to pay to get rid of them. Then just rolled them into the forest. I've seen some with old timey white sidewalls.