Microclusters of Kinked Silicon Nanowires Synthesized by a Recyclable Iodide Process for High‐Performance Lithium‐Ion Battery Anodes

Abstract

Silicon shows great promise as a high‐capacity anode material for lithium‐ion batteries. Nanostructuring silicon minimizes the impact of fracturing during charging and discharging. However, synthesizing nanostructured silicon typically requires complicated procedures with high manufacturing costs. Additionally, these complicated procedures typically have poor secondary particle formation, a requirement to achieve a high tap density. Here, a cost‐effective synthesis procedure which generates nearly ideal secondary particle clusters of nanostructured silicon is developed. The cost‐effectiveness is a result of the in operando generation of silicon iodide from iodine gas and low‐grade silicon microparticle. Decomposition of silicon iodide into crystalline silicon and iodine gas enables recycling of the iodine gas, allowing for near full reutilization of iodine in the following cycles. The optimal nanostructures and microstructures of silicon synthesized by the recyclable iodide decomposition reaction enables 83.6% capacity retention over 1000 cycles. The good performance is a result of well‐maintained morphology during cycling, enabling reutilization of the solid electrolyte interphase.

Effects of SiC and Resorcinol–Formaldehyde (RF) Carbon Coatings on Silicon-Flake-Based Anode of Lithium Ion Battery

“…However, the higher the energy density is, the more dangerous a large-scale battery system will be. Battery safety is at the highest priority especially for futuristic LIBs of very high energy and power densities [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. A desirable LIB consists of optimized combination of anode, cathode, separator, electrolyte, and packaging.…”

Ultrathin Silicon Nanolayer Implanted NixSi/Ni Nanoparticles as Superlong‐Cycle Lithium‐Ion Anode Material

“…[ 3,4 ] Thus, significant advances in terms of power density, energy density, cycle life, and safety are in need. [ 5,6 ] Among various candidate materials, silicon has long been proposed as one of the most promising anode materials for next‐generation LIBs due to its high theoretical lithium storage capacity (4200 mAh g −1 ), which is about ten times higher than that of commercial graphite (372 mAh g −1 ). [ 7,8 ] The main limitation of using Si as an anode material in LIBs is the large volume change (>400%) during electrochemical charge/discharge cycling.…”

Challenges and Recent Progress on Silicon‐Based Anode Materials for Next‐Generation Lithium‐Ion Batteries

“…Reproduced with permission. [ 94 ] Copyright 2020, Wiley‐VCH. d) Mechanical fabrication of the nanostructured Si (nano‐Si) secondary cluster.…”

“…Therefore, microclusters of kinked Si nanowires with high tap density by recyclable iodide process have been synthesized. [ 94 ] There are two merits in cyclic iodide process, including the synthesis of high‐quality Si nanowires from low‐grade Si microparticles and reuse of iodine (I 2 ). The cyclic iodide process includes formation of SiI 4 (Si(s) + 2I 2 (g) → SiI 4 (s)) and SiNWs (SiI 4 (s) → Si(s) + 2I 2 (g)).…”