content: Lithium from lithium ion batteries is also reactive with water, and moisture in the air. The key (and one of Tesla's secrets) is in its containment technologies. So, maybe we need better containment technology for hydrogen fuel cells. And also crash safety technologies (I don't know, maybe gas dispersal valves that could safely discharge the gas, or another installed tank to mix with the hydrogen gas to make it flame retardant, etc.). Also, they could always add speakers on the outside to mimic some engine noises (or elevator style easy listening music, etc.) to increase pedestrian awareness of such vehicles?