Lv Qiuliang, Liu Yuan, Ma Tianyi, Zhu Wentao, Qiu Xinping
Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University , Beijing 100084, China.
ACS Appl Mater Interfaces. 2015 Oct 28;7(42):23501-6. doi: 10.1021/acsami.5b05970. Epub 2015 Oct 19.
Silicon has been considered as a promising anode material for the next generation of lithium-ion batteries due to its high specific capacity. Its huge volume expansion during the alloying reaction with lithium spoils the stability of the interface between electrode and electrolyte, resulting in capacity degradation. Herein, we synthesized a novel hollow structured silicon material with interior space for accumulating the volume change during the lithiation. The as-prepared material shows excellent cycling stability, with a reversible capacity of ∼1650 m Ah g(-1) after 100 cycles, corresponding to 92% retention. The electrochemical impedance spectroscopy and differential scanning calorimetry were carried out to monitor the growth of SEI film, and the results confirm the stable solid electrolyte interphase film on the surface of hollow structured silicon.
由于硅具有高比容量,它被认为是下一代锂离子电池很有前景的负极材料。在与锂的合金化反应过程中,其巨大的体积膨胀破坏了电极与电解质之间界面的稳定性,导致容量衰减。在此,我们合成了一种新型的中空结构硅材料,其内部空间可用于在锂化过程中积累体积变化。所制备的材料表现出优异的循环稳定性,100次循环后可逆容量约为1650 m Ah g(-1),对应保留率为92%。进行了电化学阻抗谱和差示扫描量热法以监测SEI膜的生长,结果证实了中空结构硅表面上稳定的固体电解质界面膜。