应用恒流充放电、循环伏安、交流阻抗等测试方法,研究了不同比例的纳米碳纤维(NCF)对硫正极电化学性能的影响.结果表明,NCF-硫正极的倍率放电性能和循环伏安性能都有了一定的提高,添加量为3%和5%时效果较好.3%NCF-硫正极电流密度0.4 mA.cm-2时,比容量达880 mAh.g-1,20次循环后,比容量仍保持630 mAh.g-1.
The electrochemical performance of NCF-sulfur cathode,with different NCF contents,was investigated by constant current discharge,cyclic voltammetry and AC impedance methods.The morphologies of the cathodes were observed using scanning electron microscopy.The results indicate that the cycle life and rate capability of NCF-sulfur cathode increased.Better performance of sulfur cathode was obtained by 3% and 5% NCF conductive addition.When the current density was 0.4 mA/cm2,the 3%NCF-sulfur cathode had an initial capacity of 880 mAh/g and a reversible capacity of 630 mAh/g after 20 cycles.
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