Nanostructured Si-FeSi2-Graphite-C Composite: An Optimized and Practical Solution for Si-Based Anodes for Superior Li-Ion Batteries
- Authors
- Kwon, Hyuk-Tae; Park, Ah-Ram; Lee, Seung-Su; Cho, Hyunwoo; Jung, Heechul; Park, Cheol-Min
- Issue Date
- 26-Jun-2019
- Publisher
- ELECTROCHEMICAL SOC INC
- Citation
- JOURNAL OF THE ELECTROCHEMICAL SOCIETY, v.166, no.10, pp A2221 - A2229
- Journal Title
- JOURNAL OF THE ELECTROCHEMICAL SOCIETY
- Volume
- 166
- Number
- 10
- Start Page
- A2221
- End Page
- A2229
- URI
- https://scholarworks.bwise.kr/kumoh/handle/2020.sw.kumoh/25529
- DOI
- 10.1149/2.1401910jes
- ISSN
- 0013-4651
1945-7111
- Abstract
- To obtain anodes with a high reversible capacity, high initial coulombic efficiency (ICE), long cycle durability, and fast rate-capability for Li-ion batteries (LIBs), a nanostructured Si-based composite comprising Si, a Li-inactive FeSi2 matrix, and carbonaceous matrices was developed by combination of simple solid-state synthetic methods. Firstly, various FexSiy alloys with different atomic compositions were synthesized by simple high-energy ball milling (HEBM) and their potential as LIB anodes was investigated. Among these FexSiy alloys, the Fe10Si90 alloy (comprising Si-FeSi2) exhibited the highest first reversible capacity of 2609 mAh g(-1) and ICE of similar to 91%. To further enhance the electrochemical performance of the Si-FeSi2 alloy, a graphite-modified (Fe10Si90-graphite (Si-FeSi2-G)) composite was synthesized by using the physical force generated during HEBM, and the Si-FeSi2-G composite was further hierarchically carbon-coated (Fe10Si90-graphite-C (Si-FeSi2-G-C)) with polyvinyl chloride (PVC) by pyrolysis. The final product (Si-FeSi2-G-C composite) was comprised of well-dispersed nanocrystalline Si (active for Li) and FeSi2 (inactive for Li) within the graphite and amorphous carbon matrices. The Si-FeSi2-G-C composite exhibited excellent electrochemical performance with a high first reversible capacity of 1045 mA h g(-1), a high ICE of 87%, a long cycle durability of 925 mAh g(-1) over 80 cycles, and fast rate-capability of 700 and 550 mAh g(-1) at 1.2C and 2C rates, which meets the requirements for commercial use as a high-capacity Si-based anode for LIBs. (c) 2019 The Electrochemical Society.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Department of Materials Science and Engineering > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.