Abstract: Lithium-ion batteries (LIBs) using silicon as the anode have a higher charge-discharge capacity than those using graphite, but the repeatability of their charge-discharge cycles is extremely low. Recently, composites of silicon with graphene have been used for LIBs, but their synthesis method is complicated and needs to be improved to realize industrial applications. In this study, graphene/silicon composites are synthesized through a simple and environment-friendly method using tetraethyl orthosilicate and natural graphite as inexpensive starting materials. The resulting composite is identified through Raman spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. It is confirmed that the atomic ratio between silicon and carbon in the composite is consistent with that of the starting materials. Lithium-ion batteries are manufactured using the obtained composites as the anode material, and their charge/discharge properties are investigated. The manufactured batteries show a higher charge-discharge capacity than a graphene-anode-based battery as well as superior charge-discharge cycle characteristics as compared to a silicon-anode-based battery.

Biography: Dr. Ichiro Imae received the Bachelor, Master and Doctor degrees (Engineering) from Osaka University in 1992, 1994, and 1997. Then, he joined with Japan Advanced Institute of Science and Technology (JAIST) as an Assistant Professor. Since 2006, he is an Associate Professor of Hiroshima University. Also, he worked as an Adjunct Lecturer of Muroran Institute of Technology and a Visiting Professor of Huazhong University of Science and Technology in 2018. The details are described in his own website: https://home.hiroshima-u.ac.jp/imae/ or his Linked In account: https://www.linkedin.com/in/ichiro-imae-328438149/. If any student wants to study in his group, she/he should also check the top-page of his website.