SnO2 nanoflower arrays on an amorphous buffer layer as binder-free electrodes for flexible lithium-ion batteries

Abstract The SnO2 nanoflower arrays were firmly glued on copper collectors by an amorphous SnO2 layer deposited on Cu foils in advance, combining pulsed laser deposition and facile hydrothermal method. As a self-supported anode for Li-ion batteries, the rationally designed heterostructure exhibits excellent electrochemical performance in terms of high specific capacity, good rate capability and improved cycle stability and is successfully assembled into flexible cells made of quasi-solid electrolytes. The improved performance of as-prepared anodes can be attributed to the introducing of the SnO2 buffer layer that provides more growth sites for nanoflowers, assures the solid contact between the active materials and substrate, facilitates electron transport, and furthermore accommodates the internal strain from SnO2 nanoflowers induced by volume change during cycling. The results demonstrate that the electrode shows great promising in high performance Li-ion batteries, especially in the emerging flexible batteries.