Silicon in Hollow Carbon Nanospheres Assembled Microspheres Cross‐linked with N‐doped Carbon Fibers toward a Binder Free, High Performance, and Flexible Anode for Lithium‐Ion Batteries

Abstract Silicon (Si), as the most promising anode material, has drawn tremendous attention to substitute commercially used graphite for lithium‐ion batteries (LIBs). However, recently, the insufficiently high structural stabilities and electron/ion conductivities of silicon‐based composites have become the main concerns, hindering the further progress of silicon as the anode material for LIBs. Herein, to cope with these concerns, a binder‐free and free‐standing type anode electrode paper is fabricated from self‐assembled microspheres and intertwined fabrics, in which a 3D interconnected nitrogen/carbon network connects hollow carbon nanospheres with uniformly distributed silicon nanodots (SHCM/NCF). The as‐prepared SHCM/NCF paper maintains a reversible capacity of 1442 mAh g −1 at 1 A g −1 for 800 cycles in lithium half‐cell, and 450 mAh g −1 at 0.5 A g −1 for 200 cycles in lithium full‐cell, respectively. The excellent battery performances are mainly attributed to the free‐standing paper electrode suppressing side reactions, nitrogen/carbon networks maintaining electrical contact, and silicon nanodots alleviating the harm caused by volume expansion. Furthermore, this excellent performance combined with the simplicity of the synthesis method and the saving of excess polymer binder, current collector and conducting additives, make the designed paper exhibit great potential in practical applications.