Silicon anodes offer high theoretical capacity for lithium-ion batteries but suffer from mechanical degradation caused by large volume changes during cycling. In this study, a cross-linked polyphosphazene-based polymer binder is developed to enhance the structural stability of silicon electrodes. The binder consists of a flexible polyphosphazene backbone with carboxylic acid groups that promote strong interfacial interaction with silicon particles, together with poly(ethylene glycol) segments that facilitate lithium-ion transport within the electrode. Controlled cross-linking during electrode drying improves elastic modulus and adhesion strength while maintaining polymer flexibility. Compared to a conventional poly(acrylic acid) binder, the optimized polyphosphazene binder exhibits improved ionic conductivity, enhanced electrochemical kinetics, and superior mechanical integrity.