以玻璃纤维无纺布为基体,用高分散聚甲基丙烯酸甲酯（PMMA）包覆纳米Ti O2杂化材料（Ti O2@PMMA）进行复合,制备玻璃纤维基复合聚合物电解质膜。用SEM、热收缩、交流阻抗和充放电测试等研究复合膜的结构、热尺寸稳定性及电化学性能。玻璃纤维/Ti O2@PMMA纳米复合膜可在120-380℃保持良好的尺寸稳定性,活化后得到的复合聚合物电解质膜在室温下的离子电导率为2.88 m S/cm,与金属Li电极保持良好的界面稳定性。组装的Li Co O2/Li扣式电池在2.75-4.20 V充放电,8.0 C放电比容量可达120 m Ah/g,以不同电流共循环200次,放电容量保持率为85%。
A Si/Sn/SiOC/graphite(SSSG) composite with high efficiency and long-term cycling stability was synthesized by a cost-effective and scalable method, including the processes of mechanical milling and pyrolysis. The composite was characterized by X-ray diffraction(XRD),scanning electron microscope(SEM) and energy dispersive X-ray spectrometry(EDX). The electrochemical properties were investigated until the 25th cycle. As a result, the SSSG composite anode exhibits excellent long-term cycling stability and capacity. Such SSSG composite anode shows excellent cycling stability with a specific capacity of 568.2 mAh·g^(-1) and ~80% capacity retention over 25 cycles at 0.3C rate. The reasons for good electrochemical characteristics are considered that the SiOC net with favorable chemical stability acts as a skeleton to support and segregate Si/Sn nanostructures, and the graphitic mixing in the composite is used as conductive material to enhance the electrical conductivity in this composite. The results suggest that the design of this new structure has the potential to provide a way for the other functional composite materials.
Jian-Tao WangShi-Gang LuYao WangBin HuangJuan-Yu YangAo Tan
