[Crazy Dazz]

There's no such thing as liquid hydrogen, it doesn't exist. Even liquifying Helium is extraordinarily difficult.

As a fuel for internal combustion, Hydrogen is difficult and rather pointless. The push for Hydrogen centres around fuel-cells, and the use of non-fossil energy. Unfortunately generating Hydrogen from electrolysis of water is extremely inefficient and expensive. Ironically, the only commercially viable method of producing Hydrogen gas is by burning natural gas in such a way that only the carbon is oxidised. But of course you'd be better off just running your car on the natural gas.