High specific capacity retention of graphene/silicon nanosized sandwich structure fabricated by continuous electron beam evaporation as anode for lithium-ion batteries
Journal
Electrochimica Acta
Journal Volume
165
Pages
166-172
Date Issued
2015
Author(s)
Mori, Tatsuhiro
Hung, Tai-Feng
Mohamed, Saad Gomaa
Lin, Yi-Qiao
Lin, Hong-Zheng
Sung, James C.
Hu, Shu-Fen
Abstract
A graphene/silicon (Si) multilayer sandwich structures are fabricated using electron beam (EB) deposition without air exposure. The graphene and Si thin films are formed on Cu current correctors through a continuous process in high-vacuum EB chamber. Synthesized graphene should be suggested to the stacked multiple layer from Raman analysis. The fabricated multilayer films are used as anodes. In the beginning, the half-cell, which used a seven-layer of each thickness 50-nm graphene and Si film, exhibits good specific capacity retention over 1000 mA h g-1 after 30 charge/discharge cycles. The capacity value changed with the number of graphene and Si layers. In this study, the number of layers that exhibited optimal properties is seven. Morphological investigation showed a fine layer-by-layer structure. The relationship between different thicknesses of graphene and Si is investigated at 7 L. A 100-nm thickness exhibited optimal properties. Finally, the optimal 7 L and 100-nm thick graphene/Si exhibited high discharge capacitance >1600 mA h g-1 at a current density of 100 mA g-1 after 30 cycles. Initial coulombic and reversible efficiencies exceed 84%. The capacity retention (30th/1st discharge value) at 100 nm and 7 L exceeds 90%. Finally, the soft package battery is assembled by combining the fabricated graphene and Si electrode as anode, LiCoO2 as cathode, separator and liquid electrolyte. It can be used for commercial light-emitting diode (LED) lighting even under bending status. © 2015 Elsevier Ltd. All rights reserved.
Subjects
Anode material; Electron beam evaporation; Graphene/silicon multilayer structures; Layer-by-layer structures; Lithium-ion batteries
SDGs
Other Subjects
Anodes; Copper; Electric batteries; Electrodes; Electron beams; Evaporation; Fabrication; Film preparation; Graphene; Light emitting diodes; Lithium; Lithium alloys; Lithium compounds; Lithium-ion batteries; Multilayer films; Multilayers; Physical vapor deposition; Sandwich structures; Secondary batteries; Silicon; Anode material; Charge/discharge cycle; Electron beam evaporation; High specific capacity; Layer by layer structure; Liquid electrolytes; Multilayer structures; Specific capacities; Lithium batteries
Type
journal article