I guess Peter it is an emerging risk and one their business model may find difficult to handle.
I worked making ink using nitro cellulose a pre cursor to TNT. Like the batteries it can auto ignite and has it's on oxygen (old film stock is made of this ).
We weren't / aren't allowed to use the Chunnel & very few boats would take it. So much so that UK prouduction of the clear varnish to dilute colours was viable in the UK.
Across the RoW we shipped by truck or ocean. Containers on the top level so easily ditched.
NC storage always involved isolate buildings with water drench system to cool & control but not to kill the fire. Once it went up you let it burn.
Given that NC inks also used solved lie toluene and iso propyl aolochol some site sites major fire risks.
