Despite exhibiting high specific capacities, Si‐based anode materials suffer from poor cycle life as their volume change leads to the collapse of conductive network within the electrode. For this reason, the challenge lies in retaining the conductive network during electrochemical processes. Herein, to address this prominent issue, a cross‐linked conductive binder (CCB) is designed for commercially available silicon oxides (SiOx) anode to construct a resilient hierarchical conductive network from two aspects: on the one hand, exhibiting high electronic conductivity, CCB serves as an adaptive secondary conductive network in addition to the stiff primary conductive network (e.g., conductive carbon), facilitating faster interfacial charge transfer processes for SiOx in molecular level; on the other hand, the cross‐linked structure of CCB shows resilient mechanical properties, which maintains the integrity of the primary conductive network by preventing electrode deformation during prolonged cycling. With the aid of CCB, untreated micro‐sized SiOx anode material delivers an areal capacity of 2.1 mAh cm−2 after 250 cycles at 0.8 A g−1. The binder design strategy, as well as, the relevant concepts proposed herein, provide a new perspective toward promoting the cycling stability of high‐capacity Si‐based anodes.

The relationship between elongation at break of a material and stretching speed has always been known to be an inversed one. In this work, however, thermoplastic elastomers based on two thermodynamically immiscible components, poly­(dimethylsiloxane) (PDMS) and poly­(propylene glycol) (PPG), exhibit speed-induced extensibility (SIE). This leads to significant enhancement in Young’s modulus, strength, and elongation at break with increased stretching speed. As such, the system is capable of achieving elongation at break of more than 9000% at a 70 min–1 stretching speed and excellent notch resistance such that the strain and the fracture energy of the notched specimen can reach up to ∼2000% and ∼53,600 J/m2, respectively, surpassing the most reported PDMS-based elastomers. The toughness is also enhanced by 6.4 times merely by increasing the stretching speeds from 2 to 70 min–1. In addition, the microphase re-separation of PDMS and PPG, together with entropy elasticity of polymer chains, endows the elastomer with a good elastic recovery of ∼98%. Last, the incorporation of a reversible hydrogen bond also allows the elastomers with autonomous self-healing ability (efficiency ∼ 95%). This work opens up the possibility for developing highly stretchable and resilient materials, which can be applied in areas such as artificial muscles.

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