高度石墨化空心碳球/纳米锗复合负极材料

Highly graphitized hollow carbon sphere/germanium nanoparticles for lithium-ion battery anode material

采用高温石墨化处理和原位沉淀法,首次将高度石墨化空心碳球(HGS)与纳米锗(Ge)球复合制备锂离子电池负极材料。所制备复合材料中Ge的负载量为57.9%,表现出较高的循环稳定性和优异的倍率性能,特别是具有较高的首次库仑效率。在0.2 C下,首次充放电比容量分别为1 427.4和1 153.3 m Ah/g,首次库仑效率高达80.8%;在4 C倍率下可逆比容量可达600 m Ah/g;经过100次循环后,平均每次循环容量衰减量小于0.46%。

Highly graphitized hollow carbon spheres/nano-germanium（Ge-HGS） composites were prepared through the method of high temperature graphitization treatment and in situ precipitation. As electrode materials for lithium-ion batteries, the Ge-HGS electrode exhibits high cycling stability and excellent rate performance, especially with high initial coulombic efficiency. The first discharge and charge specific capacity are 1 427.4 and 1 153.3 mAh/g at 0.2 C, respectively, corresponding to the initial coulombic efficiency of 80.8%. Even at 4 C, the prepared Ge-HGS anode delivers the high reversible specific capacity of 600 mAh/g. From the 2 nd cycle to the 100 th cycle, the capacity loss is about 0.4% per cycle.