They are, but they have heat vents that spew off into the front, to protect the cabin itself. That is why the front of the car caught fire.
The battery itself is also segmented such that thermal runaway doesn't cause a cascade to the whole battery (which is why the driver here had ample time to continue driving and pull over).
The battery itself is also segmented such that thermal runaway doesn't cause a cascade to the whole battery (which is why the driver here had ample time to continue driving and pull over).