Preparation of Encapsulated Sn-Cu@graphite Composite Anode Materials for Lithium-Ion Batteries
Publication Type:
Journal
Authors:
Co-Authors:
Venroy Watson, Yaw Yeboah, Mark Weatherspoon, and Egwu Eric Kalu
Year Published:
2018
Abstract:
Electroless encapsulation of graphite particles with copper-tin alloy (Sn-Cu@graphite) is demonstrated
as a feasible anode preparation method that is cost effective and provides both high cyclability and
reversible capacity. Heat treatment of the electroless composites at 200 oC yielded Sn-Cu@graphite
anode composites with a 20 wt.% Sn loading, specific surface area of 22.5 m2
/g and a 1st discharge
capacity of 1074 mAh/g at 0.2C rate. In contrast, the graphite substrate particles used for the
encapsulation has a surface area of 2.34 m2
/g) and a 1st cycle discharge capacity of 327 mAh/g at 0.2 C
rate. At the 300th cycle, these capacities decreased to ~400 mAh/g and 208 mAh/g for the SnCu@graphite
and graphite substrate, respectively. Above 300 cycles, the electroless encapsulated SnCu@graphite
anode maintained a capacity higher than that determined experimentally and
theoretically for graphite. The electrochemical impedance and cyclic voltammetric results demonstrate
that the electroless encapsulated Sn-Cu@graphite anode has very low resistance and high reversible
redox reactions. The higher capacity and long term cycling (> 300 cycles) achieved with the electroless
composite anodes are attributed to the buffering effect of the electroless Cu in the Sn-Cu alloy
encapsulating graphite particles, Sn-Cu@graphite’s higher surface area (22.5 m2
/g), and curvature of
the graphite particles. The electroless encapsulated Sn-Cu graphite composite anode materials with
extended cycling have potential application for the anode of Li-ion battery.
Journal:
International Journal of Electrochemical Science
Volume:
13
Issue:
2018
Pagination:
7968-7988
ISSN:
Short Title:
Date Published:
7/5/2018
DOI: