Lawrence Livermore researchers develop new hydrogen tank

When it comes to using hydrogen as a fuel, one of the big issues is on-board storage. Most companies working on hydrogen application for cars are using compressed hydrogen gas because they don't have to deal with the issue of keeping the gas at cold temperatures to prevent boil-off. Liquid hydrogen has three time the density of compressed gas, but it must be kept below -252C. Until now, the insulated liquid hydrogen tanks have not been designed to contain the pressure of compressed gas and have had to vent off the gas as the hydrogen warms.
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]