The unique spatial arrangement of Li atoms in Li-rich compounds induces properties on Li-rich compounds, including interstitial quasiatoms, superconductivity, and superionic states. However, the dependence of increasing Li concentration on electron-phonon coupling (EPC) and superionic behavior at high pressure remains inadequately understood. Here, we systematically investigate the crystal structure of the $\mathrm{L}{\mathrm{i}}_x\mathrm{Sn}$ ($x$ = 1–8) compound at 0–150 GPa using structure prediction and first-principles calculations. Band calculations reveal that the $P6/mmm$ phases of $\mathrm{L}{\mathrm{i}}_x\mathrm{Sn}$ ($x$ = 1–7) commonly exhibits Dirac points, van Hove singularities, and flat bands. Superconducting critical temperatures ($T_{\mathrm{c}}$) were also investigated, with LiSn exhibiting a $T_{\mathrm{c}}$ of 9.3 K at 0 GPa. We further analyzed the relationship between superconductivity and EPC strength, phonon softening, linewidth, and density of states. Deep learning molecular dynamics simulations of LiSn, ${\mathrm{Li}}_2\mathrm{Sn}, {\mathrm{Li}}_3\mathrm{Sn}$, and ${\mathrm{Li}}_4\mathrm{Sn}$ demonstrate that when the Li concentration exceeds twice that of Sn, Li atoms undergo melting while Sn remains solid, indicating the emergence of a superionic state. Among them, ${\mathrm{Li}}_3\mathrm{Sn}$ exhibits the highest melting temperature of 1013 K. These findings enrich the crystal structure of Li-Sn compounds and provide a theoretical basis for constructing superconductors with a Kagome lattice and superionic states.

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• Density of states
• Electronic structure
• Phase diagrams
• Phase transitions
• Superconductivity
• Thermal properties
• 3-dimensional systems
• Alloys
• Crystal structures
• Liquids
• Metals