Growth of Silicon Particles with Various Morphology via Vapor-Solid Reaction for Lithium-Ion Battery Application

• Main Authors: Liu, Hsin-Yuan, 劉欣媛
• Other Authors: 裘性天
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/66nf2r

碩士 === 國立交通大學 === 應用化學系碩博士班 === 106 === With the development of portable electronic and electric vehicles, the energy storage device such as lithium-ion batteries (LIBs) has the advantage of high energy density are needed. As a result, LIBs have been studied in the recent years. As a promising electrode material in LIBs, Si has the advantages of its high theoretical lithium storage capacity (3579 mAh g-1), relatively low discharge potential, numerous natural abundance and environmental friendly. In this study, we report that via a simple vapor-solid reaction growth (VSRG) method to synthesize highly crystalline Si materials with different morphologies at 1023-1223K. The half-cells consisted of S800 (wire-like) showed a reversible capacity 369 mAh g-1 in EC/DMC/EMC electrolytes after 50 discharge/charge cycles at a current density of 420 mA g-1. Compared to the commercial Si particles, which demonstrated a capacity of 186 mAh g-1, the Si powders we synthesized exhibit higher reversible capacity and better cycle performance. Furthermore, the Ppy@S800 is synthesized by coating a conductive polymer, polypyrrole, on the S800 (wire-like). At the coating thickness of 50 nm, the rate capability performance is promoted to show a capacity of 158.7 mAh g-1 at a high current density (8.4 A g-1), which is three times better than uncoated samples. Ppy@S800 exhibits a reversible capacity 424 mAh g-1 in EC/DMC/EMC electrolytes after 100 discharge/charge cycles at a current density of 420 mA g-1. From the electrochemical performance, we expect the as-synthesizes silicon particles would be the potential anode material in the next generation LIBs.