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DOI: 10.1002/adma. 201504723 potential (≈ 1.5 V), which greatly restrict the battery energy density. From this perspective, developing high-capacity anode materials with low working potentials is vital to achieve high specific energy in stretchable lithium-ion batteries. Little emphasis has been thus far placed on the development of highcapacity electrode materials for stretchable lithium-ion batteries, although success in this regard would allow much higher energy density for batteries. Among the anode materials, Si can deliver 24× theoretical capacity (4200 mAh g− 1) over Li 4Ti 5O 12 and has a much lower working potential (< 0.5 V) compared with that of Li 4Ti 5O 12 (≈ 1.5 V).[7] Thus, it is highly desirable to explore Si anodes for stretchable lithium-ion batteries. Nevertheless, Si anodes have the serious issues of mechanical degradation and unstable solid-electrolyte interphase (SEI) due to the large volume expansion upon lithiation, which causes dramatic decay in battery performance.[8] Many attempts have been made to improve the electrochemical performance of Si anodes.[9] One of the most successful approaches has been the use of a self-healing polymer binder.[10] This soft and highly stretchable supramolecular polymer contains a large number of hydrogen bonding sites that allow it to mechanically heal at room temperature. The hydrogen bonding also helps the polymer adhere to the Si surface. This, combined with the self-healing ability, allows the formation of a stable SEI on Si during the large volumetric changes upon the lithiation and de-lithiation processes. This self-healing polymer is highly stretchable compared to traditional …