Laptop battery disposal

So, I've got this (Dell Inspiron) laptop battery which doesnt work anymore and I dont need a new one (I mean, I dont want to refurbish it). Where/how should it be disposed of? Is there some freepost place to send it to? I dont suppose I'm supposed to squeeze it into one of those boxes in Tenglemann!

i just threw mine in the garbage.

For those in Munich, see also the related topic: Computer, TV, and electronics disposals