A New Method for Preparing Electrospinning-Derived Carbon Nanofiber Webs with Electrodeposited Sn-Sb Alloy as an Anode Material of Lithium Ion Batteries

摘要

Electrospinning is a straightforward and low cost method for producing carbon nanofiber (CNF) webs that have interrelated pores with high surface area. The process begins with electrospinning of polyacrylonitrile (PAN) on a Cu target collector. In current production methods, the PAN nanofiber web is taken off from the collector. But in order to omit extra stages of taking off the web from a conductive collector and later putting it back on, we will try to keep the web remained on the Cu collector plate through the carbonizing heat treatment and the electrodeposition, to later use the plate as the current collector of a LIB anode. This facilitates the handling of CNFs throughout the entire process that is now much more suitable for commercialization. This unique structure is very suitable for anode materials (AMs) of Lithium Ion Batteries (LIBs). It improves the kinetics of charge/discharge cycles by reducing lithium transport paths, and creates more stable electrochemical performance by providing space for volume expansions of lithium insertions in charging cycles. CNF webs can be used as AMs, demonstrating these advantages over conventional carbonaceous materials that have long been used as the preferred choice -in spite of having a comparatively low theoretical capacity. In this study we use the CNF web as a template for electrodepositing Sn-Sb alloy, to create the mentioned structural characteristics in a coated layer of an alloy with a higher capacity. The resulting composite is shown to have a higher capacity than the substrate CNF and a good cycling performance.