Rice Husk Preparation Of Lithium-ion Battery Anode Materials

Rechargeable lithium ion batteries have a great prospect in electricindustries because of high voltage, high energy density, long cycle life, lowself-discharge ratio and goodness to environment. The development oflithium ion batteries and carbon anode materials are reviewed in detail. Thestructures and performances of carbon materials are studied, and themechanism of Li-ion inserting process is investigated. The anode carbon materials are prepared from rice husks (RH). Therelation between the electrochemical performance and the microcosmicstructure as anode materials is investigated. Rice husks are surveyed by thetemperature gravitation analysis (TGA), X-ray diffraction (XRD), Ramanspectrum, BET, SEM and its electrochemical property is characterized.Based on the results, the process of the raising temperature and experimentcondition are designed. Conclusions: 1. We determine the heat-treated process is phased according to the TGA. 2. The effect of different heat-treated rate on the microstructure and electrochemical performances is investigated. The results demonstrate that carbon materials which are amorphism, prepared by the rate of 5.0 ℃/min have higher content of H, ratio of H/C and have better electrochemical performances. 3. The effect of different heat-treated temperature on the microstructure and electrochemical performance is investigated. The results demonstrate that with the increasing heat-treated temperature carbon materials becomes more orderly. Carbon materials prepared at 700℃ have bigger specific surface areas and better electrochemical performances. -III-东北师范大学硕士学位论文 作者:郝婕 4. NaOH can remove the oxide of silicon in RH. The effect of different concentration of NaOH on the microstructure and electrochemical performances is investigated. The results demonstrate that carbon materials get higher content of C and appear (100) diffraction peak with the increasing concentration of NaOH. The carbon materials dealt with 2.0 mol/L NaOH have better electrochemical performances. The carbon material, treated at the rate of 5.0 ℃/min, at 700°C and2.0 mol/L NaOH, have the best results, the first charge and dischargespecific capacity are 678.0 m Ah/g and 239 m Ah/g respectively. The firstcharge-discharge efficiency is 35.2% and is 98.6% after ten cycles.