So I'll use your own words against you in this case - Google it.
I did.
Cut and pasted your words from your prior post.
That is how I got the fire photo.
not all of them are as evil as the media loves to tell you.
Not evil at all-------been flying with Li-po, Li-ion, Ni-cad, NIMH etc batteries for over 50 years in my R/C models----but surely can be dangerous.
As a professional fireman, I received both training, and real world experience with battery fires-------aint pretty. BTDT---- 'nuff said.
Yes, there are different batteries based on lithium chemistry------some therefore must be safer than others, and some more dangerous.
Some of the worse things that can be done to cause failure/fire in these batteries are improper charging, improper discharging, physical damage, and improper storage.
You also used the phrase
"I can see building a modified wing with the batteries spread in the wing"-------now consider this wing parked on the ramp in hot weather for a day or two. Then the owner jumps in and fires it up and takes off--------max current draw time.
Who knows what will happen??? If in a correctly designed system, with correct battery management most likely nothing will happen due to the safety systems not allowing the heat soaked batteries to even be online to run the motor.
Now, think about some homebuilder modifying his RV and filling up part of the wing area/volume with Li-ion, Li-po, or Li-whatever batteries.
Safe, reliable electric aircraft that can match the performance, range, refuel time, and usable load most likely will happen eventually------but for now it is a brave new world that awaits someone a lot more interested in being an explorer than I am.
All I am trying to say is be careful out there.