Silicon anodes require polymer binder systems that are both mechanically robust and electrochemically stable, to accommodate the dramatic volume expansion experienced during cycling operation. Herein, we report the use of a poly(acrylic acid)-grafted styrene−butadiene rubber (PAA-g-SBR) with 80% partially neutralized Na-PAA as the binder system for silicongraphite anodes. The PAA-g-SBR graft copolymer was synthesized by grafting tert-butyl acrylate onto SBR and treating the intermediate with H 3 PO 4 . The PAA-g-SBR/Na-PAA binder system was found to provide superior electrochemical performances to that of a Na-PAA/SBR system. The Na-PAA/PAA-g-SBR system had a stable capacity retention of 673 mAh g −1 for 130 cycles, while the capacity retention of the Na-PAA/SBR system was found to decline immediately. The Na-PAA/PAA-g-SBR system also displayed more preferable mechanical properties, with a lower Young's modulus value and a larger strain at failure compared to that of the Na-PAA/SBR system. Overall, these findings indicate a promising and robust polymer binder system for the application of silicon anodes in the next generation of lithium-ion batteries.