The hydrogen-powered-vehicle industry is still a nascent field that has yet to show real signs of going mainstream. Yet, major automakers are exploring the technology because it gives vehicles shorter re-fill times and longer ranges than plug-in electric vehicles. General Motors and Honda, for example, are investing $85 million as part of a joint venture to mass produce hydrogen fuel cells in 2020. Honda’s hydrogen car, the Honda Clarity, has the longest range of any zero-emission