Silicon Nanowires Grown on a Stainless Steel Fiber Cloth: A Flexible and Robust Anode for Lithium-Ion Batteries

Abstract

Silicon nanowires (Si NWs) are a promising anode material for lithium-ion batteries (LIBs) due to their high specific capacity [1]. Achieving adequate mass loadings for binder-free Si NWs is restricted by low surface area, mechanically unstable and poorly conductive current collectors (CCs), as well as complicated/expensive fabrication routes [2][3]. Herein, a tunable mass loading and dense Si NW growth on a conductive, flexible, fire-resistant, and mechanically robust interwoven stainless-steel fiber cloth (SSFC) using a simple glassware setup is reported. 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 >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 0.2 C after 200 cycles. Si NWs@SSFC anodes with different mass loadings are characterized before and after cycling by scanning and transmission electron microscopy to examine the effects of Li-cycling on the morphology. Notably, this approach allows the large-scale fabrication of robust and flexible binder-free Si NWs@SSFC architectures, making it viable for practical applications in high energy density LIBs. Figure 1. Areal capacity vs cycle number of Si NWs@SSFC with mass loadings 0.24 and 1.32mg.cm–2 at C/5 References [1] Y. Jin, B. Zhu, Z. Lu, N. Liu, J. Zhu, Adv. Energy Mater., 7 (2017), 1700715 [2] T. Kennedy, M. Brandon, K. M. Ryan, Adv. Mater., 28(2016), 5696 [3] T. D. Bogart, D. Oka, X. Lu, M. Gu, C. Wang, B. A. Korgel, ACS Nano, 8(2014), 915 Figure 1