Soft silicon anodes for lithium ion batteries

We present novel light weight three dimensional soft silicon anodes for flexible and stretchable lithium ion batteries. We employ a coaxial flexible Ni/PVDF nanofiber network as the freestanding current collector and active amorphous silicon coating to form a core-shell structure of Si/Ni/PVDF nanofibers. The soft silicon anodes show high specific capacities and good cycling life. We have demonstrated that a soft battery with the freestanding Si/Ni/PVDF membrane as an anode is capable of powering a LED at different bending states.