Somebody musta woke up on the wrong side of the lithium cell today, wow...
lol...
think about this for a second.
1. we know that lithium-ion is dangerous, we also know that there are many new formulations coming to market that are far less volatile and less apt to vent-with-flame.
2. Cars will require higher safety lithium cells than what is currently available because of the point you already made.
3. Did you forget your car has a GAS tank? if it weren't for the advancements in gas tank design, first responders and passengers would burn alive, that isn't a great way to go either... I highly doubt you'll pop the trunk of your civic and see a pile of loose cells soldered up . They will PROBABLY be in a protective cage of sorts.