Novel multi-layered 1-D nanostructure exhibiting the theoretical capacity of silicon for a super-enhanced lithium-ion battery.
Silicon/carbon (Si/C) nanocomposites have recently received much attention as Li-ion battery negative electrodes due to their mutual synergetic effects in capacity and mechanical integrity. The contribution of Si to the total capacity of the Si/C nanocomposites determines their structural efficiency. Herein, we report on a multi-layered, one-dimensional nanostructure that exhibits the theoretical specific capacity of Si in the nanocomposite. Concentrically tri-layered, compartmentalized, C-core/Si-medium/C-shell nanofibers were fabricated by triple coaxial electrospinning. The pulverization of Si was accommodated inside the C-shell, whereas the conductive pathway of the Li-ions and electrons was provided by the C-core, which was proven by ex situ Raman spectroscopy. The compartmentalized Si in between the C-core and C-shell led to excellent specific capacity at a high current rate (>820 mA h g(-1) at 12000 mA g(-1)) and the realization of the theoretical specific capacity of the Li15Si4 phase of Si nanoparticles (3627 mA h g(-1)). The electrochemical characterization and inductively coupled plasma-atomic emission spectrometry provided direct evidence of full participation of Si in the electrochemical reactions.
Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., San 14, Nongseo-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-712, Korea.
Byoung-Sun
BS
Lee
Ho-Sung
HS
Yang
Heechul
H
Jung
Seung-Yeol
SY
Jeon
Changhoon
C
Jung
Sang-Won
SW
Kim
Jihyun
J
Bae
Chwee-Lin
CL
Choong
Jungkyun
J
Im
U-In
UI
Chung
Jong-Jin
JJ
Park
Woong-Ryeol
WR
Yu