K_2CO_3添加对提高Si/C负极电化学性能的作用

本文研究了Si/C锂离子电池负极材料中K_2CO_3的添加对提高电极电化学性能的作用及其作用机理。采用恒流充放电测试和电化学阻抗谱(EIS)研究了不同K_2CO_3添加量对Si/C负极电化学性能的影响;通过扫描电镜(SEM)和傅里叶红外光谱(FTIR)等方法分析了K_2CO_3添加对Si/C负极在循环过程中结构和成分变化的影响。研究结果表明,加入K_2CO_3后,由于电极在循环过程中结构稳定性增强以及电极的固体电解质界面(SEI)膜阻抗和电荷转移阻抗减少,使Si/C负极的循环稳定性和倍率性能得到明显提高。

Enhanced Electrochemical Performance of Si/C Anodes for Lithium-ion Batteries by Addition of K2CO3

Effect and mechanism of the addition of K2CO3 in Si/C anodes for lithium-ion batteries on the improvement of electrochemical properties are investigated.Effects of the contents of K2CO3 on the electrochemical performance of Si/C anodes are investigated by galvanostatical charge and discharge test and by electrochemical impedance spectroscopy (EIS).Structure and composition changes of the Si/C electrodes during cycling are analyzed by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR).Results show that the cycling stability and high-rate capability of the Si/C anode are obviously improved by the addition of K2CO3,which is attributed to the improved stability of the structure of the electrode,the decreased solid electrolyte interface (SEI) resistance and charge transfer resistance of the anode.