High Pressure Hydrogen Storage in Carbon Nanotubes

Hydrogen storage for transportation is one of the most important problems faced in implementing a “hydrogen economy”. Hydrogen can be produced in many ways, but then must be stored for use by fuel cells. The U.S. Department of Energy’s Hydrogen, Fuel Cells & Infrastructure Technologies Program has set hydrogen storage goals to be achieved by 2015. New technologies and storage materials are required to meet these goals if a hydrogen economy is to be realized. The gravimetric capacity goal for hydrogen storage materials is set at nine weight percent hydrogen (net useful energy/max system mass). Experiments using carbon nanotubes, and other materials such as metal hydrides, metal organic frameworks and other carbon nanostructures have shown promise as hydrogen storage material, but not to the level required to meet DOE’s goals. 

LLNL has developed an apparatus and method for high pressure hydrogen storage within multi-walled carbon nanotubes (MWCNT) exposed to ambient air pressure that promises to meet these goals.