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以马铃薯淀粉为炭源,制备硅-石墨/炭复合负极材料,研究复合材料中硅/石墨比例、负极片制备过程中粘结剂种类、调浆溶剂种类和pH值对材料电化学性能的影响,并对影响机理进行初步探讨,采用红外光谱法和扫描电镜分别对材料结构和形态进行表征,恒流充放电法测定材料的电化学性能。结果表明:当复合材料中硅/石墨比例为4∶8,羟甲基纤维素钠做粘结剂,pH=3的柠檬酸-氢氧化剂缓冲液做调浆溶剂时,复合材料经50次循环后可逆容量达到890mAh/g,容量保持率为95%,这是由于粘结剂和硅颗粒之间形成的酯键可使电极片在充放电过程中保持很好的完整性,从而显示出良好的电化学性能。
Graphite / carbon composite negative electrode material was prepared by using potato starch as carbon source. The effects of binder type, slurrying solvent type and pH on the electrochemical properties of the composite were investigated. , And preliminary study on the mechanism of influence was carried out. The structure and morphology of the material were characterized by infrared spectroscopy and scanning electron microscopy, respectively. The electrochemical performance of the material was measured by constant current charge-discharge method. The results show that when the ratio of silicon to graphite in the composite material is 4: 8, sodium hydroxymethyl cellulose as a binder and citric acid-hydroxide buffer with pH = 3 as the slurrying solvent, the composite material is subjected to 50 cycles After the reversible capacity of 890mAh / g, 95% capacity retention, which is due to the bond formed between the binder and the silicon particles can make the electrode plate in charge and discharge process to maintain good integrity, which shows good The electrochemical performance.