(26b) Evaluation of Sorption System for Hydrogen Storage

Significant R&D efforts are being pursued globally to improve the efficiency and economics of onboard hydrogen storage systems for mobile applications. The sorption of hydrogen on or in a solid substrate, relying either on physisorption or chemisorption or even a combination of both offers a potential alternative means of storing hydrogen. Hydrogen storage via physisorption on porous materials, such as activated carbon, carbon nanostructures and metal organic frameworks (MOFs) is particularly enticing due to its inherent reversibility and cyclability. Moreover, these materials exhibit fast kinetics and operate at relatively low storage pressures. However, hydrogen physisorption at ambient temperatures on currently available porous materials leads to unacceptably low hydrogen storage densities. Acceptable densities are only attainable at cryogenic temperatures.

We will present the results of our evaluation of an adsorption-based hydrogen storage tank for vehicular application. We will discuss the net storage capacity of the system over wide temperature and pressure ranges, the thermal requirements to charge and discharge hydrogen at the desired flow rates, and dormancy.