Consider the relative volumetric and gravure tricks energy densities of 7500 psi compressed hydrogen versus liquid hydrogen. Which would be a better candidate for a fuel cell bus? And why.
You seem concerned with how to store hydrogen. It is one of the issues with a fuel cell vehicle. Another is where the hydrogen is coming from . Presently 96% of hydrogen is made from fossil fuels. The infrastructure is in place and this is the most economical method. Without legislation it is unlikely that hydrogen will be obtained in any other way. What is the likelihood of banning fossil fuels in making hydrogen when the petrochemical industry controls congress? So asking which way is best to store hydrogen for a fuel cell bus is a bit like asking if you would rather be shot or hung. There is no free hydrogen on Earth. It combines too readily with other elements. Using hydrogen is already less efficient than using the original source of energy that is required to separate hydrogen from other chemical compounds. Adding compression or liquification even further lowers the energy return on energy investment. Eventually we may see a method of chemically combining and storing hydrogen but it would have to be some kind of a miracle to make hydrogen anything but a wasted energy fuel.
Hydrogen embrittlement is why you should NOT be considering a fuel cell of this nature. Look it up.
Again Breath on the wind has the right answer, storing hydrogen as a liquid is rocket science and even NASA gets it wrong sometimes.
