A team at Lawrence Livermore lab has now developed a carbon-fiber wrapped and better-insulated tank that can take either gaseous or liquefied hydrogen. The new tank design has passed safety tests including impact and flame tests. When installed in a Toyota Prius modified to run on hydrogen, compressed gas gives it a range of 80 miles. If it's filled with liquid hydrogen the range goes to 200 miles. The thermal performance has improved from venting fuel vapor after 3-4 days to going at least 6 days and perhaps as much as 15 days. Unfortunately, even 15 days really isn't particularly good. While the extra density of liquid hydrogen is desirable, it simply doesn't seem like a very viable option.
[Source: Lawrence Livermore Laboratory, via EcoGeek]