Recently, our group has prepared a series of new double perovskite materials (Li1.5La1.5MO6, M=W6+, Te6+) which display interesting electrochemical behaviour for use in Li-ion batteries. The unconventional location of Li ions in the W compound have recently been found to be distributed between the octahedral BB' sites and in La-vacant A-sites. We have shown that this compound shows great promise as an anode material, while the Te analogue displays excellent solid state electrolyte properties. To develop a more complete understanding of why these materials display such attractive properties, we propose the use of total scattering experiments to elucidate the local atomic arrangements across a family of these structural analogues. Such studies will be highly complementary to our existing Li-diffusion work and complete a vital structural study of the Li ion location in these materials.