Intercalated compounds offer a versatile platform for high-temperature superconductivity, as exemplified by sodium-intercalated graphite ($\mathrm{Na}{\mathrm{C}}_8$) with a transition temperature ($T_{\mathrm{c}}$) above 28 K. However, the microscopic origins of their structural robustness and superconducting behavior remain elusive. Here we establish a unified framework integrating stacking geometry, intercalated-cation chemistry, bonding topology, and pressure tuning to uncover the mechanisms governing stability and superconductivity. Through extensive first-principles investigations of 36 designed B-N compounds intercalated with $s$-, $p$-, and early $d$-block cations, we propose an electrogeometric stabilization mechanism in which structural robustness arises from the cooperative balance between optimal charge donation filling bonding σ states and geometric compatibility with the interlayer spacing. This balance enhances lattice rigidity and regulates electron-phonon coupling and band dispersion, thereby governing the superconducting behavior. Notably, the $R\text{−}3m$ phase of $\mathrm{Na}{\mathrm{B}}_2{\mathrm{N}}_2$ exhibits a predicted $T_{\mathrm{c}}$ of $\sim 40.6\mathrm{K}$; evolutionary searches further indicate its feasible synthesis. These findings establish fundamental design principles for realizing high-$T_{\mathrm{c}}$ superconductivity in intercalated materials.

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• Chemical bonding
• Electrical properties
• High-pressure studies
• Superconductivity
• First-principles calculations