One-Step Electrochemical Growth of a Three-Dimensional Sn-Ni@PEO Nanotube Array as a High Performance Lithium-Ion Battery Anode

Various well-designed nanostructures have been proposed to optimize the electrode systems of lithium-ion batteries for problems like Li+ diffusion, electron transport, and large volume changes so as to fulfill effective capacity utilization and increase electrode stability. Here, a novel three-dimensional (3D) hybrid SnNi@PEO nanotube array is synthesized as a high performance anode for a lithium-ion battery through a simple one-step electrodeposition for the first time. Superior to the traditional stepwise synthesis processes of heterostructured nanomaterials, this one-step method is more suitable for practical applications. The electrode morphology is well preserved after repeated Li+ insertion and extraction, indicating that the positive synergistic effect of the alloy nanotube array and 3D ultrathin PEO coating could authentically optimize the current volume-expansion electrode system. The electrochemistry results further confirm that the superiority of the SnNi@PEO nanotube array electrode could largely boost durable high reversible capacities and superior rate performances compared to a SnNi nanowire array. This proposed ternary hybrid structure is proven to be an ideal candidate for the development of high performance anodes for lithium-ion batteries.