How can I dispose of my portable charger (battery) as a tourist in Japan?

My portable charger has cracked where one of the cells has started to expand. This makes it a dangerous fire hazard. I only have a couple of days left and I can't take it on the plane. Does anyone know how I can dispose of it when I can't access any household waste services? Thanks.

Edit: Thanks everyone! I was able to get a new one at Anker and they directed me to dispose of the old one at Yamada for 550 yen, which I was happy to pay. Anker also taped it up with insulating tape in the meantime. Everyone was extremely helpful especially since my Japanese is very minimal.

by LateBiloomer