Galvanostatical Performance of Rice Derived Carbon Coated Silica as Anode for Lithium Ion Batteries

Abstract

Rice derived carbon coated silica powder with various silica/rice weight ratios was prepared by drying and then pyrolysing the co-milled slurry mixture thereof and incorporated into the anode as active material for lithium ion batteries. The crystallinity of the composites was characterized by X-ray diffraction analysis. Coin type cells (2032) were manufactured and galvanostatically tested, including charge-discharge characteristics, cyclic voltammograms and electrochemical impedance spectra. The composite anode with rice/silica ratio of 1:1 delivers a better initial discharge capacity, Coulombic efficiency and 10th-cycle capacity retention of 454.2 mAhg-1, 48.5% and 35.1%, respectively, at the potential window of 0.02-2.5 V and constant current density of 50 mAg-1. Good reversible capacity as high as 207.9 mAhg-1 and cyclic stability were achieved for the rice-carbon anode with rice precursor annealed at 700 oC/3 h, followed by 900 oC/1.5 h in argon atmosphere as active material.