【摘要】 研究了水溶性的LA132粘接剂的pH值对LiFePO4电极性能的影响。通过滴定法测定了不同pH值的LA132对LiFePO4正极材料中Fe2+百分含量的影响,使用充放电测试、交流阻抗、X射线衍射、扫描电镜测试手段对不同pH值下电极的物理以及电化学性能进行表征分析。研究表明LiFePO4在LA132粘接剂呈酸性的条件下能够有效抑制Fe2+被氧化,在碱性条件下Fe2+容易被氧化成Fe3+,当LA132的pH显弱酸性时,LiFePO4电极表现出最好的性能,具有较小的阻抗,较高的放电比容量和循环稳定性。更多还原

【Abstract】 In this paper,the effect of the pH values of aqueous binder LA132 on the performance of the LiFePO4 cathode was researched.Here the effect of different pH values on the Fe2+ percentage of LiFePO4 cathode was researched via titration method,and then the physical and electrochemical properties of LiFePO4 cathode with various pH values were investigated by using constant current charge/discharge test,electrochemical impedance spectra(EIS),X-ray diffraction(XRD) and scanning electron microscopy(SEM).It is found that Fe2+ of LiFePO4 can not be readily oxidized in acidic solvent rather than in alkaline solvent.Moreover,when the LA132 displays faintly acid,the LiFePO4 cathode shows the most excellent performance,such as lower impedance,higher discharge capacity and more excellent cycling stability.更多还原