Due to its large capacity in theory, red phosphorus (RP) has become a viable anode choice for lithium-ion batteries (LIBs), but because of its inherent attributes, for instance, substantial volume expansion during cycling, which causes capacity degradation and electrode pulverization, it is difficult to use in real applications. To address these challenges, this study investigates the modification of red phosphorus-based electrodes through P/Se heterointerface engineering and conductive network design. The theoretical calculation shows that the introduction of selenium reduces the band gap of P/Se. While forming the P/Se heterogeneous interface enhances the cyclic stability of the composites, it simultaneously boosts the surface pseudocapacitive effect of the materials. The introduction of activated carbon builds an admirable conductive network. The resulting composite electrode, denoted as P/Se@C, exhibits promising electrochemical performance. After 800 cycles, P/Se@C composite retains a stable capacity of 541.1 mAh/g at 200?mA g?1. Furthermore, even after 1500 cycles, P/Se@C composite retains a capacity of 408.3 mAh/g at 1000?mA g?1.