锂离子电池碳包覆锡负极性能研究

应用水热法分解葡萄糖制作锂离子电池碳包覆锡负极. 充放电测试表明，添加5%（by mass）乙炔黑导电剂的该电极初始放电比容量达967 mAh.g^-1，经50周循环其放电比容量仍保持362 mAh.g^-1，远高于锡电极的比容量（50周循环166 mAh.g^-1）. 碳包覆可防止锡粉团聚，降低锡的不可逆容量损失. 而添加乙炔黑可降低碳包覆电极与电解液间的交流阻抗，改善电极内部锂离子及电子的传导通道，从而也提高了该电极的初始放电比容量.

Properties of Carbon Coated Tin Negative Electrode for Lithium-ion Battery

Carbon coated tin power was prepared by decomposing glucose applying a hydrothermal method, and was further used as the active material for negative electrode of lithium secondary battery. Charge-discharge tests show that the carbon coated tin electrode with the addition of 5 wt.% acetylene black as a conductive agent could obtain an initial discharge capacity of 967 mAh.g^-1 and a discharge capacity of 362 mAh.g^-1 after 50 cycles, which is much higher than that of tin electrode (166 mAh.g^-1 after 50 cycles). The coated carbon hinders the agglomeration of tin powder, reduces the irreversible capacity loss of tin; the addition of acetylene black could reduce the impedance between the electrode and the electrolyte, therefore, improve the transfer property of lithium ions and the electrons within the electrode, which contribute to the higher initial discharge capacity.