Sodium and lithium intercalated C60 have been recently demonstrated to be a new class of hydrogen absorbers thanks to their capacity to dissociate H2 molecule at moderate pressure and temperature through a spill-over like effect. Pure phase of Li6C60 can store up to 5 mass% H2 at 100 bar with an onset temperature of 270 °C.During the last 4 years we successfully studied the in situ gas sorption by means of neutron powder diffraction at ANSTO (Sydney,AU). More recently, we also investigated the mixed phases NaxLi6-xC60, in order to find the best compromise between kinetics and absorption. Unfortunately, the low pressure allowed in ANSTO facility (P < 60 bar D2) significantly limited the hydrogenation window to less than half of the maximum achievable value. This permitted us to investigate only the first stages of H2 absorption, while the complete process remained an open question.