Southpark:
It's good to store those battery packs in bunker boxes. Also, when charging them, it can be beneficial and a good idea to put them in a purpose-built metal box - in case anything bad happens during charging.
Indeed, in a previous incident I almost set fire to my wokshop, a LiPo was chaging on the bench and something went wrong.
The large (1500mAhr+) RC model ones I now charge in one of the fireproof bags and even that is on a stone tile.