Dense Silicon Nanowire Networks Grown on a Stainless Steel Fiber Cloth: A Flexible and Robust Anode for Lithium-ion Batteries

Silicon nanowires (Si NWs) have great promise as an anode material for lithium-ion batteries (LIBs) due to their very high specific capacity. Achieving adequate mass loadings for binder-free Si NWs have been restricted by low surface area, mechanically unstable and poorly conductive current collectors (CC), as well as complicated and expensive fabrication routes. Herein, we report a tunable mass loading and dense Si NW growth on a highly conductive, flexible, fire-resistant and mechanically robust interwoven stainless steel fiber cloth (SSFC) using a simple glassware setup. The SSFC CC facilitates dense growth of Si NWs where its open structure allows a buffer space for expansion/contraction during Li-cycling. The Si NWs@SSFC anode displays a stable performance for 500 cycles with an average Coulombic efficiency of more than 99.5%. Galvanostatic cycling of the Si NWs@SSFC anode with a mass loading of 1.32 mg.cm-2 achieves a stable areal capacity of ∼2 mAh.cm-2 at 0.2C after 200 cycles. Si NWs@SSFC anodes with different mass loadings were characterized before and after cycling by SEM and TEM to examine the effects of Li-cycling on the morphology. Notably, our approach allows the large-scale fabrication of robust and flexible binder-free Si NWs@SSFC architectures, which makes it viable for practical applications in high energy density LIBs. This article is protected by copyright. All rights reserved.