The morphology evolution and hygroscopicity reduction of Y2MO3O12 crystal are investigated by introducing (LiMg)(3+). With increasing the content of (LiMg)(3+), the hygroscopicity of Y2MO3O12 is reduced obviously depending on the XRD, Raman and DSC/TG results, and the morphology of Y2MO3O12 transforms remarkably from amorphous crystal to octahedra and then rod. The results suggest the effects of (LiMg)(3+) on repelling water molecules and improving the growth of Y2MO3O12 crystal, which could be a reflection of the decrease of micro-channels in the structure. Some (LiMg)(3+) substitute Y3+ in Y2MO3O12 to form solid solutions of (LiMg)(2-x)YxMo3O12 with octahedra and then rod, and excess (LiMg)(3+) leads to the formation of (LiMg)(2)Mo3O12 due to the difficulty in substituting Y3+ with (LiMg)(3+). The substitution of Y3+ for (LiMg)(3+) reduces the thermal expansion coefficient of Li-ion battery material of (LiMg)(2)Mo3O12. (C) 2015 Elsevier Ltd. All rights reserved.