Fuel cell technology being developed by several automakers, namely Honda and Chevy, is a non-combustion form of energy unlike liquid hydrogen which essentially uses the same engine structure as conventional cars. This require liquid hydrogen to be kept in the vehicle at 420 degrees below zero which is costly. In fuel cells, hydrogen based cells are kept on stacks. A hydrogen - oxygen reaction creates electricity that powers the car. The fuel cells are refilled with the hydrogen chemical.
hydrogen fuel cells operate more efficiently than hydrogen internal combustion engines, and you don't have to store the hydrogen at liquid temperature. you can get a good range without using liquid hydrogen (at least in 10 years you can).
