Improving Cycle Stability of Silicon as Anodic Electrode for Lithium Ion Batteries

• Main Authors: Chiang, Heng-Wei, 江恒瑋
• Other Authors: Chia-Chun Chen
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/75986224870828128725

碩士 === 國立臺灣師範大學 === 化學系 === 101 === Silicon as anode for Lithium ion batteries (LIB) has attracted much attention due to its high capacity (4200 mAh g-1). However, the worst disadvantage is large volume expansion during lithiation resulting in fast fading of the capacity of silicon. In this study, silicon anodic electrodes in have been successfully prepared and the performance of the LIB also has been optimized via tuning different experimental parameters such as different binders and different volume of solvent. The fabrication of silicon anodic electrode slurry were based on using nano-silicon (100nm), carbon black (Super P), sodium carboxymethyl cellulose (Na-CMC) and a pH=3 buffer solution as active materials, conductive carbon, binder and solvent, respectively. In addition, we also utilized graphene nanoplatelets(GnPs) to replace carbon black and added 10wt. % Fluoroethylene carbonate(FEC) and 2wt. % Vinylene carbonate (VC) into liquid electrolyte for improving the conductivity and stability of silicon anodic electrode, thus reducing the irreversible capacity of cycles. Finally, the cycle stability of Si-LIB were improve to 175 cycles with a limited discharge capacity of 1500 mAhg-1 at a rate of 1000mAg-1 both in discharge and charge process, respectively. In order to evaluate the influence of the cycling rate on electrochemical properties, cells were also cycled by 200 mAg-1.