I'll toss in here as it seems everyone skipped on by it.
Sure, anything & everything creates toxic gases / fumes when it burns... DOH !
The crap in your house, Furniture, foams, plastics, materials, carpets etc... creates far more toxic smoke that will knock you out in mere seconds & kill you fast if there is a fire than anything coming from a battery pack. Ask ANY fireman about how toxic house fires are. I, unfortunately, inhaled such toxic smoke in a fire for about 1.5 minutes before being dragged out, my lungs never recovered !, I survived not everyone did.
Lithium Cells such as LiPo, MNC, NCA (NOT LFP) can catch fire, explode and cause thermal runaway situations and therefore they are "Packaged" accordingly in commercial packs. They are also NOT to be installed within the Residential Areas because of that fact. LFP on the other hand does not do such things and many places allow them to be installed inside (with provisions for safety).