Theoretical studies on hydrogen adsorption properties of silicon-lithium binary clusters are carried out. We have considered three different clusters viz., Si₅Li$^{−5}$, Si₅Li⁶ and Si₅Li$^+_7$ and for each cluster, the geometries of different possible isomers are optimized. In all the minimum energy isomers of the three clusters considered, two of the lithium atoms are found to be situated in the axial positions and the remaining lithium atoms are in the equatorial position in the Si₅ plane. The lithium atoms which are in Si₅ plane are bonded to the Si-Si edge through a bridged bond instead of a corner in the Si5 ring. From the calculated atomic charges, it is found that there is a charge transfer from lithium to silicon leaving a partial positive charge on the Li atoms and the axial lithium atoms are more charged as compared to the remaining lithium atoms. In the case of Si₅Li₆ and Si₅Li$^+_7$, the Li sites can trap a total of 14 and 17 H₂ molecules, respectively, with each bridge bonded Li site adsorbing three H₂ molecules and each axial Li adsorbing one H₂ molecule which corresponds to a gravimetric density of 13.33 wt% and 15.25 wt%, respectively.