Mechanochemical synthesis of Si/Cu3Si-based composite as negative electrode materials for lithium ion battery

Shang-Chieh Hou; Tsan-Yao Chen; Yu-Hsien Wu; Hung-Yuan Chen; Xin-Dian Lin; Yu-Qi Chen; Jow-Lay Huang; Chia-Chin Chang

doi:10.1038/s41598-018-30703-3

Mechanochemical synthesis of Si/Cu₃Si-based composite as negative electrode materials for lithium ion battery

Sci Rep. 2018 Aug 23;8(1):12695. doi: 10.1038/s41598-018-30703-3.

Authors

Shang-Chieh Hou¹, Tsan-Yao Chen², Yu-Hsien Wu³, Hung-Yuan Chen³, Xin-Dian Lin³, Yu-Qi Chen³, Jow-Lay Huang^{4

5

6}, Chia-Chin Chang^{7

8}

Affiliations

¹ Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
² Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 30013, Taiwan.
³ Department of Greenergy, National University of Tainan, Tainan, 70005, Taiwan.
⁴ Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan. jlh888@mail.ncku.edu.tw.
⁵ Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan, 70101, Taiwan. jlh888@mail.ncku.edu.tw.
⁶ Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan, 70101, Taiwan. jlh888@mail.ncku.edu.tw.
⁷ Department of Greenergy, National University of Tainan, Tainan, 70005, Taiwan. ccchang@mail.nutn.edu.tw.
⁸ Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan, 70101, Taiwan. ccchang@mail.nutn.edu.tw.

Abstract

Mechanochemical synthesis of Si/Cu₃Si-based composite as negative electrode materials for lithium ion battery is investigated. Results indicate that CuO is decomposed and alloyed with Si forming amorphous Cu-Si solid solution due to high energy impacting during high energy mechanical milling (HEMM). Upon carbonization at 800 °C, heating energy induces Cu₃Si to crystallize in nanocrystalline/amorphous Si-rich matrix enhancing composite rigidity and conductivity. In addition, residual carbon formed on outside surface of composite powder as a buff space further alleviates volume change upon lithiation/delithiation. Thus, coin cell made of C-coated Si/Cu₃Si-based composite as negative electrode (active materials loading, 2.3 mg cm^-2) conducted at 100 mA g^-1 performs the initial charge capacity of 1812 mAh g^-1 (4.08 mAh cm^-2) columbic efficiency of 83.7% and retained charge capacity of 1470 mAh g^-1 (3.31 mAh cm^-2) at the end of the 100^th cycle, opening a promised window as negative electrode materials for lithium ion batteries.