The problem is even though we have gotten miraculously stable lithium batteries, they still aren't 'bulletproof' enough that explosion and fire risks are negligible. Add 3x more energy to it and it starts becoming a really big problem. This is what has kept 99.9% of these miraculous battery technologies we always hear about, too dangerous to use in consumer devices.
If it is as stable, or preferably more stable, than current tech, great! If it is anything less, you will never see it except in maybe industrial applications.
Industrial Applications, as Tesla has shown in Australia & Puerto Rico, are still a magnificent boon to society, so I hope they roll-out the more dangerous iterations sooner than later.
Yes, it requires oxygen, which happens to be all around and inside a vehicle typically. I'm not sure what your point is. If a fuel tank is ruptured it can lead to fire and/or explosion. If a battery is ruptured the risk of fire is a lot less. Maybe batteries carry a greater risk of spontaneously combusting, but I don't think that makes them more dangerous than carrying a tank of flammable liquid around
Petrol is very safe for the energy density it has due to the relatively slow rate at which outside oxygen gets fed into the flame causing a burn rather than explosion. TNT is far less energy dense (1/5 iirc) but because it contains oxygen it is far more dangerous and explosive. A very high energy density battery is likely to be closer to TNT in its reaction and not have the requirement of needing outside oxigen to keep the reaction speed in check (but really this depends on the exact technology of the battery)
... like the DOE, ARPA, USDA, and NSF? They all are, I've personally worked on projects funded by these organizations to make carbon neutral petrol replacements. Heck, even the oil majors are funding that kind of work, they see the writing on the wall even if politicians play-act that the fossil fuel party will continue indefinitely.
If it is as stable, or preferably more stable, than current tech, great! If it is anything less, you will never see it except in maybe industrial applications.