Silicon (Si) is a promising anode material in advanced high-energy-density lithium-ion batteries (LIBs) due to its large theoretical capacity of 4200 mAh g^-1, however, the high volume change cause the pulverization and unstable solid-state interface layer. How to maintain the structural integrity and high electronic conductivity during cycling is the major challenge for high-capacity Si anodes. Binder plays a key role in maintaining the mechanical integrity of electrodes in lithium-ion batteries. However, the existing binders typically exhibit poor stretchability or low conductivity at large strains, which are not suitable for high rate and high-capacity silicon (Si)-based anodes undergoing severe volume changes during cycling. Herein, we report a novel stretchable conductive polymer that possesses inherent high conductivity, excellent stretchablity and ductility. The polymer can be stretched up to 400% in volume and 250% in length without conductivity loss and mechanical fracture. The Si anode composed of the polymer and Si nanoparticles exhibited excellent cycle performance with a high discharge capacity (1500 mAh g^-1 for over 700 cycles) as well as high areal capacity (5.13 mAh cm^-2). The highly stretchable conductive binder provides a new perspective for designing next-generation high-capacity and high-power batteries.

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