Or, you charge it up fully, stab it with a knife just for fun (somewhere outside), and after it stops erupting and has cooled down THEN put it in the trash.
The whole 'recycle batteries properly' thing comes from lead-acid and nickel-cadmium batteries, that definitely should never end up in landfill, due to the toxic heavy metals. Lead is poisonous, and cadmium is very poisonous. Lithium and copper, not really.
Though, I wouldn't want to breathe the smoke from a Li-Ion battery on fire.