Architecting SiC@g-C3N4 composites with built-in stress dissipation for high-performance lithium-ion batteries

Silicon-based anodes are expected to significantly enhance the energy density of lithium-ion batteries due to their high theoretical capacity. However, repeated fragmentation and reconstruction of the SEI layer, driven by substantial mechanical stress, have considerably constrained its practical application. To dissipate the substantial mechanical stress, we introduce a flexible lamellar material (g-C 3 N 4 ). The flexible g-C 3 N 4 effectively dissipates the substantial mechanical stress induced by significant volume expansion between SiC particles, thereby significantly improving the mechanical strength of the SiC electrode, maintaining its structure, and promoting the formation of a mechanically robust, highly ion-conductive SEI layer. AFM test demonstrates that the introduction of g-C 3 N 4 effectively dissipates the substantial mechanical stress. Specifically, compared to the SiC electrode (8.8 keV), the SiC@5 % g-C 3 N 4 electrode (4.0 keV) exhibits considerably lower energy dissipation.