Electrochimica Acta 54 (2009) 5884–5888
Electrochimica Acta
journal homepage: www.elsevier.com/locate/electacta
Study of copper foam-supported Sn thin film as a high-capacity anode for
lithium-ion batteries
a
a
a,∗
a
a
a,b
Qingyu Li , Sijiang Hu , Hongqiang Wang , Fangping Wang , Xinxian Zhong , Xinyu Wang
a
School of Chemistry and Chemistry Engineering, Guangxi Normal University, Yucai Road, Guilin 541004, PR China
School of Metallurgy Science and Engineering, Central South University, Changsha 410083, PR China
b
a r t i c l e i n f o
a b s t r a c t
Article history:
Three-dimensional porous Sn thin film electrodes were prepared by electroless deposition on copper
foam, then its morphology and electrochemical property were studied by means of scanning electron
microscope (SEM), X-ray diffraction (XRD), electrochemical cycling test and cyclic voltammetry (CV). The
porous framework and micro-holes have shown a great structure advantage in restricting severe volume
changes when the Sn thin film was employed as anode for lithium-ion battery. The film electrode of
Received 2 March 2009
Received in revised form 7 May 2009
Accepted 13 May 2009
Available online 21 May 2009
−1
sample C with an initial capacity of 676 mAh g showed good cycle performance displayed by retaining
Keywords:
Sn thin film
Negative electrode
Electroless deposition
Copper foam
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a capacity of 313 mAh g after 100 cycles.
©
2009 Elsevier Ltd. All rights reserved.
Lithium-ion batteries
1
. Introduction
In this paper, we report the preparation of three-dimensional
porous Sn thin film material by electroless deposition on the cop-
per foam. The electrochemical properties of the Sn thin film as an
anode material in lithium-ion batteries have been investigated. In
brief, the new anode design can offer a good conductivity to keep
the stability of electrodes and largely improve cycle-life of the mate-
rials.
Lithium-ion batteries with a high energy density have been
used for electric devices and electronic vehicles. The capacity of
graphite as a negative electrode, which is mainly used in commer-
cialized production of lithium-ion batteries, is now approaching
−1
the theoretical value of LiC6 (372 mAh g ). In order to improve
the performance of lithium-ion batteries, new high-capacity anode
materials are required. Tin was widely studied as an alternative
anode material for lithium-ion batteries because of its excellent
capacity [1–9]. However, the cycle performance was poor due to
the severe volume change during lithium insertion and extraction
processes. It was reported that the volume per Sn atom of Li22Sn5
was nearly three times larger than that of Sn [10]. Therefore, to
display the outstanding capacity of Sn anode, new materials that
can buffer the large volume change are needed. Recently, some
three-dimensional porous materials, such as hollow carbon, cel-
lular silicon and copper foam [11–14], were used as collectors to
enhance the cycle-life of active anode materials. Porous materials
can be deposited on substrate through a lot of methods. For exam-
ple, electrodeposition, electroless deposition and laser spraying. In
comparison, electroless deposition presents excellent advantages
2. Experimental
Before electroless plating, copper foam substrate was pre-
treated in alkaline solution and dilute hydrochloric acid solution
to remove oil and oxide on the surface. Optimal synthesis
parameters were obtained through orthogonal test: SnCl ·2H O
2
2
−1
−1
−1
(
10 g L ), NaH PO ·2H O (10 g L ), CS(NH ) (70 g L ), concen-
2
2
2
2
2
−1
trated hydrochloric acid (36 wt.%, 5.6 mL L ). Three types of
thickness-controlled Sn thin films were deposited for 90 s (sam-
◦
ple A), 60 s (sample B), and 30 s (sample C) at 60 C, respectively.
The as-prepared samples were characterized by field emission
scanning electron microscopy (FE-SEM, LEO-1530), with addi-
tional semiquantitative information obtained using large area
standardless energy dispersive spectroscopy (EDS) and X-ray
diffraction (XRD, Rigaku X-ray diffractometer equipped, Cu K␣ radi-
ation).
After deposition and washing, the Sn thin film electrodes were
◦
dried under vacuum at 80 C for 24 h. Subsequently button-type
∗ Corresponding author. Tel.: +86 773 3310900; fax: +86 773 5854077.
2032 cells were constructed in an argon-filled dry box with Sn thin
film electrodes and lithium foil. The anode was separated from the
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013-4686/$ – see front matter © 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.electacta.2009.05.051