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We directly prepared a novel hybrid anode of modified polyvinyl alcohol(PVA)polymer/silicon nanoparticles(Si NPs)/multiwall carbon nanotubes(CNTs)nanofibers on the current collector via water-based electrospinning.This environmental-friendly and feasible direct deposit method using water as solvent enables to eliminate using of both toxic solvents like N-Methyl-2-pyrrolidone and by-passes conventional paste preparation steps such as sonication,blending,grinding and doctor-blade coating.From modifying PVA polymer in the PVA/Si/CNTs by heat treatment under air atmosphere,the hybrid Si assemblies have very promising battery performance by solving the decay of Si nanoparticles.The half-cells using hybrid Si assemblies exhibited an outstanding initial discharge capacity of 4,100 mAh/g cycled at 0.25 A/g due to the synergy by well-dispersed Si NPs and CNTs in the PVA matrix.At a fast charging/discharging rate of 2.5 A/g,the hybrid Si assemblies showed excellent capacity retention of about 93%for 300 cycles.Such improvement of cycle life should be attributed to supporting and protecting Si NPs by modified PVA polymer,which suppresses the volume expansion or pulverization of the Si NPs and the formation of solid electrolyte interface(SEI)layers on the Si surfaces.Furthermore,the hybrid Si assemblies have very high capacities at fast charge/discharge rates such as 1,193 mAh/g at 5 A/g,945 mAh/g at 7.5 A/g and 708 mAh/g at 12.5 A/g owing to good cooperation highly conductive carbon nanotubes in this hybrid system.The full cell using hybrid anode and LiCoO2 cathode possesses a stable capacity retention of 100%during 100 cycles.