Hydrogen storage materials are provided that may be capable of a hydrogenated state and dehydrogenated state. The hydrogen storage material comprises a plurality of hydrogen storage molecular units. Each hydrogen storage molecular unit comprises a transition metal bonded to one or more elements from period 2 of the periodic table, wherein the hydrogen storage material includes at least 6.5% molecular hydrogen by weight when in the hydrogenated state and is stable at temperatures below about 200° C. and at pressures of about 1 atm and below. The hydrogen storage materials may be used in conjunction with fuel cells in portable electronic devices.