Elastic behavior of crystalline Li-Sn phases with increasing Li concentration

► We study the elastic properties of Li-Sn alloys as a function of Li concentration. ► B, E, G and ν of isotropic structures decrease linearly with Li concentration. ► Highly lithiated phases are significantly softer. ► For values of y ≈ 0.7 highly anisotropic structures deviate from linearity. ► The softening is consistent with the increase in the population of ionic bonds.